ARMED police have stormed a home in Surrey in connection with the “Mother of Satan” nail bomb on a packed Tube train at Parsons Green after a teen was arrested in Dover.

Cops detained the 18-year-old boy this morning at the port and he is currently being quizzed over terror offences at a local police station.

75 Police raided an address in Sunbury-on-Thames in Surrey in connection with the Parsons Green attack Credit: London News Pictures

75 Masked officers have been seen coming from a house on the quiet cul-de-sac Credit: London News Pictures

75 Forensic officers on the street today Credit: Darren Fletcher - The Sun

75 Residents said they had "one minute" to get out of their houses Credit: Darren Fletcher - The Sun

75 A 100m cordon has been set up on the road Credit: Darren Fletcher - The Sun

75 It comes as a "very significant" arrest was made Credit: Reuters

Gun cops are now raiding a home belonging to an MBE foster couple in leafy Sunbury-on-Thames in Surrey as part of the investigation into the terror attack.

Ronald, 88, and Penelope Jones, 71, have fostered hundreds of children over more than 30 years.

Terrified residents were told they had "one minute" to get out of their houses as police evacuated homes on the quiet cul-de-sac at around 1.40pm today.

Officers from the Metropolitan police and Surrey police have put a 100m cordon in place in the area, which is a 37 minute train ride from Wimbledon - where the bombed Tube started its journey.

A Met spokesman said: "A search of the address is ongoing and the cordons will remain in place until the operation is complete.

"Police would like to thank the local residents directly affected for their cooperation and patience. Local officers are on duty in the immediate area to talk to the community and address any concerns that they may have.

"No further arrests have been made."

75 Onlookers watch as police conduct a raid on a property on Cavendish Road Credit: Getty Images - Getty

75 Police officers stand by. Cordons will remain in place until the operation is complete Credit: Getty Images - Getty

75 A resident waits with here dog outside the police cordon Credit: EPA

75 A forensic officer walks down Cavendish Road Credit: Getty Images - Getty

75 Cops on the quiet cul-de-sac today as a raid was carried out Credit: Reuters

75 Police swooped at around 1.40pm today Credit: Reuters

75 It comes after a "very significant arrest" was made this morning Credit: Storyful

75 Residents have been evacuated and a 100m cordon is in place Credit: Storyful

Officers told residents they must wait “at least a few hours” before they could return to their homes, and directed them to the nearby Staines Rugby Club.

Cavendish Road resident Alan Clarke said armed police had given him a matter of minutes to evacuate.

"I feel very shocked. It does make me feel unsafe to be honest.

"I was asleep on the sofa when I heard a bang on the window and this armed police man all balaclavered up said 'please can you evacuate'."

Mr Clarke said he had been given only 10 minutes to leave his property and no explanation as to what it was all about.

He said he had no idea how long it would be before he could return home.

75 An 18-year-old boy was arrested in Dover today in connection with the attack Credit: Chris Eades

Local Mojgan Jamali said: "I was in my house with my children and there was a knock at the door from the police.

"They told me to leave. They said: 'You have one minute to get out of the house and get away.'

"I just got out, I got my three children and we left the house and the street."

The mum, 33, said she didn't know where to go, so decided to take her children - aged between five and 10 - to the shops.

She said: "I had to do something to keep them entertained and to keep their minds off it - it's obviously pretty scary. I'm trying to keep them calm.

"I hope this gets settled soon, that we can get back to normal."

She said there had been an increased police presence on the street since Friday, adding: "I only had to open the door and I saw police everywhere."

75 Home Secretary Amber Rudd said the arrest was "very significant" Credit: Chris Eades

75 The teen was held at the port of Dover where ferries run hourly to Europe Credit: Chris Eades

75 Armed police have swooped on a cul-de-sac in Sunbury-on-Thames in Surrey

75 Wires can been seen hanging out of a bucket inside a carrier bag on a District Line train

Home Secretary Amber Rudd has described this morning's arrest as "very significant".

Deputy Assistant Commissioner Neil Basu, Senior National Coordinator for Counter Terrorism Policing, said: “We have made a significant arrest in our investigation this morning. Although we are pleased with the progress made, this investigation continues and the threat level remains at critical.

“The public should remain vigilant as our staff, officers and partners continue to work through this complex investigation. We are not, at this time, changing our protective security measures and the steps taken to free up extra armed officers remain in place.

“This arrest will lead to more activity from our officers. For strong investigative reasons we will not give any more details on the man we arrested at this stage.”

75 A woman injured in the blast is treated by paramedics as police say most of the injured suffered flash burns

Police were also seen searching bins outside Dover Priory railway station on Saturday afternoon prompting suggestions the suspect may have arrived in the town by train.

The station also has CCTV cameras positioned in and outside the building.

The station is a 30 minute walk to the port.

Police officers also searched industrial bins at the Dover ferry passenger terminal.

Officers were pictured lifting plastic carrier bags out of the bin and examining them before putting them back.

The Met also revealed this morning that 45 witnesses have come forward and a further 77 have sent video and images to officers.

Port authorities in Dover refused to comment on the arrest of the teen, who will be moved to a South London police station later today.

Ferries from the port travel hourly to Europe with services to Calais starting from £50 and ships to Dunkirk costing £39.

What we know so far:

A homemade bucket bomb connected to a timer sent a "fireball" hurtling through an eastbound District Line Tube at Parsons Green at around 8.20am on Friday

29 people have been taken to four hospitals across London including a young boy believed to have suffered serious burns to his legs

The bomb is thought to have been packed with nails and "Mother of Satan" explosive triacetone triperoxide

Cops said they are hunting the bomber and possible accomplices and have arrested an 18-year-old boy at the port of Dover

Armed cops swoop on foster home owned by MBE couple as part of investigation

Theresa May raised UK terror threat level to "critical" - meaning another attack may be imminent

ISIS claimed responsibility for the blast and praised "jihadi squad"

The army and 1,000 extra armed police officers to patrol UK streets

Train services have now restarted and the station is open once more

Metropolitan Police Commissioner Cressida Dick said "London will not be stopped by terror" following the "absolutely appalling, horrendous" bombing.

She added: "The great thing about London is that we don't give in, we don't give in to terrorists - we never have and we carry on."

Home Secretary Amber Rudd said the Joint Terrorism Analysis Centre had told her the terror threat level will remain at critical.

She urged the public to remain "vigilant, not alarmed" as she explained it is too soon to know whether those responsible for the tube bomb were known to the authorities.

75 Police have stepped up security after a bucket bomb blast on a Parsons Green Tube yesterday Credit: London News Pictures

75 Armed police have been seen patrolling train stations across the UK as the terror threat level was raised to critical Credit: London News Pictures

75 Gun cops have also been seen outside a shopping centre in Brighton after the bomb blast injured 29 people Credit: EDDIE MITCHELL 07771605974

75 A young woman is seen with a bandage on her face following the Tube blast Credit: Reuters

75 Soldiers and 1,000 extra armed cops have been drafted in after the threat level was raised Credit: PA:Press Association

75 Aerial footage shows police on the scene after the homemade bomb detonated Credit: AP:Associated Press

It comes after Theresa May raised the UK terror threat level to "critical" amid fears the “cowardly” extremists behind the Parsons Green blast could strike again.

Security has now been beefed up across the UK, with 1,000 extra armed cops patrolling UK streets and train stations in the wake of the terror attack.

Officers holding guns were also seen at football matches today as Britain remained on high alert.

Terror cops confirmed they are hunting multiple attackers after ISIS claimed a jihadi "squad" was behind the explosion that sent a "fireball" through a packed carriage.

The crude DIY bomb, packed with nails and screws, was reportedly made with TATP, an explosive also known as “Mother of Satan”.

Traumatised witnesses told how they saw a baby "close to the wall of flames” that sent blood-soaked commuters running for their lives at rush-hour.

The Prime Minister said troops are being sent to guard nuclear power stations and other key sites, freeing up 1,000 more armed cops to patrol the streets following the attack.

“The Joint Terrorism Analysis Centre has now decided to raise the national threat level from severe to critical - this means their assessment is that a further attack may be imminent," she said.

75 Theresa May announced Britain’s terror threat level has been raised to "critical" Credit: Sky TV

75 There was increased security in London today as a result of the terror threat being raised Credit: London News Pictures

75 Parsons Green station re-opened this morning as police could be seen on the platforms Credit: Darren Fletcher - The Sun

75 But it was business as usual as people made their way into the station Credit: Darren Fletcher - The Sun

75 Defiant Londoners refused to let the terror attack scare them as they waited for trains at Parsons Green Credit: Darren Fletcher - The Sun

75 More police will be present at Underground stations after the threat level was raised to critical Credit: Darren Fletcher - The Sun

75 Extra gun cops patrolling the streets of the Capital will also be seen Credit: London News Pictures

75 Armed cops rushed to the scene, where panicked commuters had fled from Parsons Green Station Credit: AFP or licensors

75 ISIS said a splinter group is behind the attack

"The public will see more armed police on our transport network and streets to provide extra protection.”

Mrs May’s announcement marked the first time since May’s Manchester Arena bombing that the threat level has been at its highest.

Experts say the bucket bomb could have killed dozens but a suspected faulty timer detonated earlier than planned and failed to ignite the main bomb.

The device, which is being examined by Ministry of Defence scientists, was similar to the failed bombs in the July 21 attacks on the London transport network in 2005.

Former army bomb disposal officer Chris Hunter said the Parsons Green bomb is likely to have been made with TATP – an explosive used by Al-Qaeda and ISIS terrorists.

75 An injured woman is seen being escorted from the scene by paramedics Credit: Reuters

75 A woman wrapped in a blanket is helped by firefighters and paramedics this morning after a home-made bomb exploded on the Tube

75 A young boy was comforted after the attack Credit: @gacv80

75 Aerial footage shows police at the scene of the blast Credit: AP:Associated Press

He told The Times: “This substance is known as the Mother of Satan. It is super sensitive just after being made and can go off very easily.”

ISIS's official Amaq News Agency announced that a jihadi "squad"carried out the attack and praised those responsible.

Met Assistant Commissioner Mark Rowley said a manhunt is underway for the bomber and possible accomplices.

He confirmed that they are "we are only aware of one device" following earlier reports that a second bomb was planted.

75 The ten-year-old can be seen with burns on his legs Credit: YouTube

75 An injured schoolboy is carried from the scene by a firefighter after passengers reported a 'fireball' on a train Credit: Twitter

The homemade bucket bomb device sent a "fireball down a carriage" as it partially detonated, with a schoolboy and pregnant woman among those injured.

Medical student Michael Perry said he treated a “terrified” boy of around nine or ten-years-old who was bleeding and bruised after being caught up in the stampede.

Mr Perry, 29, told The Times he heard “screams and wailing” as he arrived at the station.

“He had a massive scrape and bleeding and contusion on his forehead where he had been knocked forward, as well as gashes on his tummy and side where he had been stepped on.

75 A woman is led from the scene after being treated by paramedics amid reports 29 were injured in the attack Credit: PA:Press Association

75 Armed cops are seen aboard the Tube as a counter-terror investigation is launched and bomb squads called in Credit: Reuters

75 Counter-terror cops pictured at the scene as they officially took charge of the investigation Credit: Reuters

“He had lost his brother, Robert, and was absolutely terrified and worried about him.”

The homemade bomb has been likened to pressure-cooker devices used in 2013's Boston Marathon attack, which killed three and injured hundreds.

These were packed with nails and ball-bearings to cause maximum damage, and it is not yet clear if yesterday's device had similar projectiles.

More on the Parsons Green terror attack Live Blog TUBE TERROR BLAST LIVE Britain terror threat 'critical' after explosion - follow the latest updates here 'WHAT IS THE WORLD COMING TO?' Passengers 'took SELFIES' amid stampede for the exit after Tube explosion TERROR CRUSH Men climbed over kids as they fled Tube blast in human stampede that saw pregnant women crushed, witnesses claim 'SECOND BOMB' PANIC Commuters sparked rumours of a ANOTHER tube bomb after ditching their bags during blast 'IT GOES BOOM!" Sick ISIS supporters celebrate London bucket bomb and claim it was a TRIAL RUN for bigger attack 'BURNED FROM TOP TO TOE' BBC's Sophie Raworth reveals horror injuries of Parsons Green terror victims stretchered from explosion TUBE BLAST Here's what we know about the Parsons Green bombing and the police investigation LONDON UNITED Cabbies offer FREE rides and Good Samaritans open up their homes to commuters caught up in Parsons Green blast STATION DRAMA Cops Taser man at Birmingham new Street Station as Britain remains on edge after Parsons Green terror attack 'THE RICH DON'T DIE' Marco Pierre White Jr posts sick message boasting he avoids terror attacks because he's too rich to take the Tube

The explosion follows four previous attacks in 2017, which saw five innocent people killed in Westminster in March and 22 killed in the Ariana Grande bombing in Manchester in May.

A further eight were killed in a van and knife rampage on London Bridge in June, and one man killed when a van rammed into worshippers outside a North London mosque.

Donald Trump hinted that the attacker may have been known to security services in a string of Tweets posted yesterday morning. The Met Police later said the US President's posts were "pure speculation" and "unhelpful".

Theresa May later hit out at Trump, saying: "I never think it's helpful for anybody to speculate on what is an ongoing investigation."

75 An injured woman is comforted outside Parsons Green Tube station this morning as police confirmed the explosion was a terrorist act Credit: Reuters

75 An injured woman is taken away by stretcher as cops put a wide cordon around the area and called in specialists Credit: Harry Cole/ The Sun

75 Commuters fled the scene after a fireball came down a carriage after a bucket bomb partially detonated

75 Pictures taken on the District Line carriage showed the home-made device inside a Lidl bag Credit: AP

At about 8.20am on Friday, people fled the station screaming as the blast sent flames flying, with a Metro reporter at the scene saying people are "really badly burned" adding that "their hair was coming off".

An onlooker said a "fireball flew down a carriage" with panicked commuters diving out an open door at the South West London station.

Lauren Hubbard, 24, who was on the train, said: “I heard a loud bang. There was a wall of fire that came towards me. I could feel the heat. We ran for it and then hid.

“There was a baby closer to the fireball — I just hope they are okay. There were loads of children. "Everybody was screaming. My first thought was ‘terrorist incident’. I just ran.”

WHAT WAS THE REAL TARGET? Parsons Green attack could have been much worse THE Parsons Green terrorist’s real target could have been major London stations including Paddington and Westminster, according to terror experts. Will Geddes, CEO of security consultants ICP, told SunOnline the homemade bomb could have been intended for busier stops for “maximum impact”. "My feeling is Parsons Green was not the intended destination for this device,” he said. “We have to remember the terrorist is looking for maximum publicity and recognition worldwide. "Unless you have been to Parsons Green, or you know someone there or are a Londoner you will not know it. "Wimbledon, Notting Hill and Paddington - there are other destinations on that line that would have had much greater impact."

75 Experts believe Parsons Green may not have been the intended target of the terror attack

Sarah Hickson, 31, who was crushed in the stampede, described scenes of chaos after the rush-hour explosion.

“People started shouting, ‘There’s a man, there’s a man’ and everyone started running. It was just sheer panic.

“A pregnant woman and a schoolboy in front of me were being crushed on the concrete stairs.”

A picture taken on the District Line train shows a burning plastic bucket with what appear to be wires coming from it.

The device had been placed in a foil-lined Lidl cool bag and left by the Tube carriage door. The budget supermarket has since confirmed it will support investigations into the attack.

75 An extra 1,000 armed cops will be patrolling Britain's streets Credit: Reuters

75 There will be an increased police presence at stations this weekend Credit: PA:Press Association

75 Operation Temperer will see military personnel replacing police at key sites Credit: Rex Features

75 Extra armed cops have been being drafted in

NHS England confirmed the total number of people treated at hospitals after the bombing has risen to 29.

Some 21 people were still being treated at 5.30pm on Friday for burns and injuries suffered in the stampede to escape the station.

Eight others have already been discharged.

A young boy is reportedly among the worst injured, with witnesses reporting he had serious burns to his legs.

It is believed some of those hurt may have been caught in the crush as panicked commuters fled the station.

75 Parsons Green station is in South West London, and experts believe the attacker may have intended to target more well-known areas

75 Forensic teams are on the scene in South West London this morning following the horror blast that injured 29 Credit: AFP

75 Emergency services are at the scene where 29 people were injured

75 Armed cops are at the scene following this morning's blast as pictures of a suspected device emerge Credit: Reuters

75 A passenger on the Tube posted a picture on twitter of his 'charred head' Credit: Twitter

75 Shocked commuters outside Parsons Green Station this morning as emergency services respond to the blast Credit: Reuters

To the man that pulled me out of the pile of people on the stairs during the stampede at Parsons Green - thank you. Thank you so much. — Katherine Manson (@KatherineManson) September 15, 2017

Home Secretary Amber Rudd condemned the blast, saying: "Once more people going about their everyday lives have been targeted in a callous and indiscriminate way."

Responding to the attack London Mayor Sadiq Khan said the city "utterly condemns the hideous individuals who attempt to use terror to harm us and destroy our way of life."

He confirmed this morning that Parsons Green has since been reopened as he thanked Transport for London and the Met Police.

Were you on the London Underground train? Email emma.lake@the-sun.co.uk or 02077824360

75

75 Cops comfort those caught up in the blast amid reports about 20 people have been injured Credit: Reuters

75 A police officer treats an injured woman outside Parsons Green station this morning Credit: Metro.co.uk / Solo Syndication

75 Bomb teams have arrived at the scene in South London as a wide cordon is put in place Credit: Reuters

Passengers told of having to "run for their lives" after the blast, while others claimed victims were left with "facial and leg injuries".

Lucy, 24, who works in PR, got separated from her boyfriend Fabian, 29, in the panic after the explosion.

They were on their way to work just three carriages away from the blast.

She told The Sun Online: "We didn't hear the blast, we just heard screaming.

"The people started running from the Tube. It was a stampede.

"There was a crush on the stairs. People at the bottom were telling us to go back towards the platform, I don't know whether they were staff or commuters.

"I saw an injured little boy, he must have been about 10, being carried away crying.

"I'm so shaken. We thought it was terror immediately. I never thought this would happen to us, so close to home."

75 Firefighters have put a wide cordon in place at the scene this morning Credit: AFP

75 Bomb squads are reportedly making a second suspected device safe Credit: AFP or licensors

'IT WAS ABSOLUTE CHAOS' - SUN MAN HARRY COLE DESCRIBES CHAOS AT PARSONS GREEN "Everyone came running out the station and you could see people were visibly shaken. "There's currently a police helicopter hovering overhead and a huge emergency service presence

"The cordon is getting bigger and bigger now and armed police are on the scene. "More than 100 people were flooding from the station. "They are being taken to the actual green and you can see people are in tears and hugging each other. "It's absolute chaos."

Fabian added: "I saw people with burns. It was horrible.

"I got separated from Lucy on the stairs and panicked.

"We were just on our way to work and planning what to do together tonight. Then this.

"Once we made it out of the station people's belongings were littered everywhere. There were bags, shoes all over the place.

"We started gathering stuff to hand in to the police. They were there within minutes. It was all such a blur.

"You could tell by the fear in peoples' eyes that something really bad had happened."

Georgia Anile, 20, lives two streets away from the station and told Sun Online: "I saw a woman being stretchered away. She had really bad burns to her legs."

Luke Walmsley was on the Tube at the time of the blast. He told Sky News: "As it pulled into Parsons Green slowing down there was a loud noise and saw the remnants of a flash and smoke.

TERROR ALERT: What do the threat levels mean? Threat levels are designed to give a broad indication of the likelihood of a terrorist attack. LOW means an attack is unlikely. MODERATE means an attack is possible, but not likely SUBSTANTIAL means an attack is a strong possibility SEVERE means an attack is highly likely CRITICAL means an attack is expected imminently

"There was a stampede, hordes of people just running to me. Within 5 seconds it was apparent it was not a safe place to be.

"As the doors opened people were running down the platform. Down the stairs. But there was a backlog because the barriers wouldn't open. So there was a big crush, people shouting, 'has he got a knife, is there an assailant'.

"It was every man for himself when that happened. [There were] no sign of clothing on some [because of burns]. Serious hand and leg injures.

"It was so busy, loads of school children. So many nannies trying to find children. People filming it, taking pictures, no real sign that anyone called the emergency services.

"Firemen came running down the platform, but members of the public began getting water onto burns.

"They just said it was like a fire ball or a fire blast. It smelt like burning hair. Burning skin. It was like a large match had gone off, and in that instant people just started sprinting to the exit."

75 Police dogs have been called to the scene following the blast Credit: AFP

75 Armed cops are on the scene after a 'bucket bomb' partially detonated on the Tube this morning Credit: AFP

75 Theresa May will chair an emergency Cobra meeting this afternoon as the emergency service scramble to the scene Credit: Reuters

A BBC reporter said she saw a woman taken to hospital with burns "from top to toe" amid the chaos.

Sophie Raworth added: "I have just seen a woman who was just there, she was just stretchered out.

"Her legs are wrapped up and she has been burnt, she has burns to her face, she was conscious, she was taking some pain relief and some oxygen but clearly people have sustained burns.

"She seemed to have burns all over her body from top to toe."

Sylvain Pennec, a software developer from Southfields, near Wimbledon, was around 10 metres from the source of the explosion when fire filled the carriage.

He said: "I heard a boom and when I looked there were flames all around," he said. "People started to run but we were lucky to be stopping at Parsons Green as the door started to open."

He described the scene of panic as commuters struggled to escape the carriage, "collapsing and pushing" each other.

Mr Pennec stayed behind to take a closer look at what he believed was the source of the explosion.

"It looked like a bucket of mayonnaise," he said. "I'm not sure if it was a chemical reaction or something else, but it looked home made. I'm not an expert though."

Another witness said: "It was absolute chaos, no I didn't hear anything just everyone started running and screaming."

Third fail 'work of amateur' By Ben Leo THE Parsons Green bomb is the third that failed to devastate Tube trains. On July 21, 2005 — two weeks after 7/7 — bombs at Oval, Shepherd’s Bush and Warren Street failed when only the detonators exploded. And last October student Damon Smith, 20, left a dud device on a Jubilee Line train. Chris Phillips, ex-head of the UK’s National Counter Terrorism Security Office, said of yesterday’s bid: “It is almost certainly an explosive where the mix wasn’t right, or has gone off. “It meant the device flared rather than exploded. It is possible the detonator caused that. “This style of bomb can be built for a few hundred pounds with ingredients bought online. It feels like an amateur’s work.” BIG Brother star Marco Pierre White Jr apologised after tweeting “this is why I don’t take the tube #therichdontdie”.

75 Credit: AFP

75 Emergency services are at the scene in South West London Credit: PA:Press Association

A man tweeted a picture of his charred head after being caught up in the attack as the injured were shown being treated at the scene.

Sun reporter Harry Cole, who is at the scene, said: "Everyone came running out the station after reports of an explosion on the platform.

"You could see people were visibly shaken and hundreds were flooding out as armed police ran towards the station.

"There's currently a police helicopter hovering overhead and a huge emergency serviced presence.

"The cordon is getting bigger and bigger now.

"More than 100 people were easily running from the station after the reports came in as it was peak time.

"They are being taken to the actual green and you can see people are in tears and hugging each other.

"It's absolute chaos."

A woman who was on the Tube told 5live: "I was in the carriage next to it or the one along as the screaming as it happened it felt really, really loud.

"There was one lady as I came out having a bottle of water tipped over her face and hands.

"I was on the phone to my mum and she said 'leave the area and go home'. I felt very British I lost my shoe but I went to get it. I'm a bit shaken up."

Photos posted on social media showed a huge emergency services presence with London Ambulance Service and the London Fire Brigade scrambled.

75 Commuters said they were told of a 'security incident' as services were shut down this morning Credit: PA:Press Association

75 Commuters reported people suffering severe facial burns Credit: Twitter

75 The suspected device appears to have been left next to carriage doors Credit: AP:Associated Press

75 Armed cops and counter-terror officers are at the scene in South West London Credit: Reuters

75 Commuters flee Parsons Green station as emergency services arrive on the scene

The incident comes after figures revealed terror-related arrests in Great Britain have hit a new record high, with suspects held at a rate of more than one every day.

Police warned there is no such thing as a "typical terrorist" after official statistics showed rises in numbers detained across ethnicity and age groups.

There were 379 arrests for terrorism-related offences in the year ending June 2017, the highest number in a 12-month period since data collection began in 2001.

Police and MI5 are running 500 investigations involving 3,000 individuals at any one time, while there are also 20,000 former "subjects of interest" whose risk must be kept under review.

Anyone who has information that would assist detectives is urged to contact the hotline 0800 789 321, if you have any images from the scene then please upload them to www.ukpoliceimageappeal.co.uk