
Police investigating the Bangkok bomb blast have released CCTV footage of a suspect reportedly spotted placing a bag at the scene moments before the explosion that killed at least 21 people and injured more than 120 others.

Images show the man carrying a rucksack near the Erawan Shrine in the popular Ratchaprasong district of the capital then leaving the area without it around 15 minutes before the blast.

Thai junta chief Prayut Chan-O-Cha said the suspect, who was wearing a yellow T-shirt and thick-rimmed glasses, was believed to be from an 'anti-government group based in Thailand's north-east' - the heartland of the kingdom's anti-coup Red Shirt movement.

He described the bombing as the 'worst ever attack' on his country.

'Today there is a suspect who appeared on CCTV but it's not clear... we are looking for this guy,' he said, according to AFP.

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Is this the bomber? Police investigating the Bangkok blast have released these CCTV images of a suspect carrying a rucksack near the Erawan Shrine in the popular Ratchaprasong district of the capital then leaving the area without it around 15 minutes before the explosion

A man who was seen 15 minutes before the explosion placing a bag at the shrine is being treated as a possible suspect

Aerial shots of the scene show the extent of the damage done by the bomb to the shrine and its surroundings

Police continue to scour the scene for evidence on the morning after an explosion in Bangkok. Charred debris is seen littered across the ground

The new lead comes as a video shot by a witness showing flames engulfing a Bangkok shopping district after a loud bang erupted from the nearby site, which is popular with tourists, emerged.

The scene descends into chaos as people are heard screaming, including a woman and a baby, and are seen running away.

A man walking along the Skybridge captured the moment on his camera phone and is heard yelling in a panic.

Witnesses say the heat of the deadly blast was suffocating, debris flew everywhere and they were surrounded by ash.

The footage has surfaced as Thai officials continue to work at Erawan Shrine to identify bodies and scour the scene for evidence.

In photographs taken on Tuesday morning, the shrine remains cordoned off to the public and charred debris lies on the ground.

No one has taken responsibility for the blast but the suspect who was seen placing a bag inside the shrine before the explosion is being investigated by police.

The New York Times had earlier reported that an officer at the scene, who spoke on the condition of anonymity, said the suspect was a woman - who was overheard speaking Thai - was being treated as a possible suspect.

The newspaper also quoted rescue worker Winai Petploy as saying that two other unexploded bombs were also found within the shrine, contained within small travel bags.

So far the death toll stands at 22 and 123 people injured, police spokesman Prawut Thavornsiri confirmed to AFP. But local reports suggest the toll could rise.

Crowds of people are seen wandering along the Skybridge before the blast (left) and following the blast a fiery inferno engulfs the overpass (centre and right)

A mobile snap shared by China's Xinhua News Agency shows a group of men trying to revive a bombing victim on a sidewalk

Glass covering an advertising billboard near the shrine - in Ratchaprasong district of Bangkok - was shattered by the explosion

Chaos: Members of the Explosive Ordnance Disposal (EOD) squad and Thai forensic police officers inspect the explosion site on Monday evening

She was overheard speaking Thai by witnesses, according to a police officer who wished to remain anonymous

A police dog is seen sniffing through the debris at the shrine following the horrific blast the morning following the tragedy

Two barefoot monks cross the road near the scene of the explosion on Tuesday morning, away from the police chaos

Explosion: Four foreigners are believed to be among the dead after an attack the Thai government says was designed to damage the country's vital tourist industry

A TIMELINE OF RECENT BLASTS IN THE THAI CAPITAL: HOW BANGKOK HAS BEEN SUBJECTED TO OTHER EXPLOSIONS

A Thai soldier patrols the Central World shopping mall building - just yards from where today's attack occurred - after it was set on fire by anti-government 'red shirt' protesters in Bangkok in 2010 2010 - April: Five grenade blasts hit Bangkok, targeting hundreds of pro-government supporters in attacks that leave one dead and scores wounded, including foreigners. The grenade blasts come after a failed attempt by authorities to disperse the Red Shirts, sparking clashes that left 25 people dead and more than 800 injured in the worst civil unrest in almost two decades. July: The government says a bomb that killed one at a bus stop in central Bangkok was designed to create disorder. September: Bangkok put on high alert after a series of grenade blasts. Thousands of police and soldiers are mobilised for extra security. October: A blast at an apartment complex kills four, with the government blaming the incident on the anti-government 'Red Shirt' movement. The Reds deny any involvement and accuse the authorities of a plot to justify tougher security powers. November: A grenade is thrown onto a minibus killing one. It was not clear if it was politically motivated. 2011 - January: Police arrest five men armed with explosives after a tip-off that bomb attacks were planned near the seat of government in Bangkok. June: Two people are injured in a blast at a political protest by Thailand's 'Yellow Shirt' demonstrators near Government House. December: A makeshift explosive device is found and defused near the government lottery office with authorities saying the perpetrators wanted to 'challenge the government'. 2013 - May: A homemade bomb hidden near rubbish bins in a busy suburban Bangkok shopping area explodes, injuring seven people. 2014 - January 18: One protester dies after a bomb attack at an opposition march in Bangkok. Authorities and demonstrators blame each other for the blast, which was apparently caused by a grenade-type device thrown from a nearby building. January 19: Twin blasts by unknown attackers at an anti-government protest in central Bangkok leave 28 injured. 2015 - February: Two small bombs explode near a popular shopping mall in downtown Bangkok. One man is injured but there are no deaths. August 17: At least 21 people - among them foreigners - are killed after a blast in Chidlom district at a popular shrine located on a main road through Bangkok's commercial hub Advertisement

Describing the scene of devastation, paramedic Marko Cunningham said: 'It was like a meat market. There were bodies everywhere. Some were shredded. There were legs where heads were supposed to be. It was horrific.'

Thai junta chief Prayut Chan-O-Cha has confirmed police were chasing a suspect seen in CCTV footage

A former British paratrooper who is no stranger to horrific scenes having served in Afghanistan, Iraq and Kosovo described the scenes as a 'massacre'.

John McMahon told the Mirror he had seen worse but it was a 'very bad' scene, with 'body parts everywhere'.

'People were running away injured and crying. Others were sitting in shock. It was horrific. There was rubble and fires everywhere,' the 33-year-old Liverpudlian said.

Police Chief Somyot Poompummuang told The Bangkok Post gunpowder was crammed into a pipe and set off as a bomb similar to TNT.

But there were conflicting reports last night over whether the bomb was smuggled into the shrine and left under a bench or strapped to a motorcycle parked outside, causing several passing cars to explode.

The Bangkok Post quoted police as saying that the bomb was left inside the shrine and an electronic circuit suspected to have been used in the attack later found 30 yards away.

Four foreigners are believed to be among those killed in the attack, which the Thai government claims was designed to damage the country's vital tourist industry.

Many victims were probably visiting the shrine or several shopping centres in the area when the attack took place.

Security video showed a powerful flash as the bomb exploded and then chaos as those that were able to ran for their lives while others began tending to the wounded.

Following the blast, police have confirmed two Chinese, two Hong Kong nationals, two Malaysians, one Singaporean and five Thais were among the dead, according to The Strait Times.

As the city centre was sealed off and Thailand's government set up a 'war room', dozens of ambulances took the injured to hospital. White sheets covered bodies beside the Erawan Shrine while charred motorcycles littered the blood-stained ground.

Prawut Thavornsiri said the blast - the deadliest single assault in recent years - was likely to have been politically motivated and designed to bring 'chaos'.

Deputy Prime Minister Prawit Wongsuwon said: 'We still don't know for sure who did this and why. We are not sure if it is politically motivated, but they aim to harm our economy and we will hunt them down.'

Carnage: Scorched motorbikes where at least 21 are dead and another 123 are injured after a huge explosion in Bangkok during rush hour

Scenes of devastation: A policeman photographs debris from the explosion which occurred in central Bangkok, Thailand

Deadly: The explosion took place in the popular Ratchaprasong district in the heart of the Thai capital about 7pm local time on Monday

Dramatic: Witnesses said victims were 'blown to pieces' after the explosion in one of the Thai capital's most popular tourist hotspots

Emergency: The blast rocked the popular Rachaprasong district in the heart of the Thai capital during rush hour on August 17

Distressing: One man learns of the devastation and speaks on the phone after the blast at the Hindu shrine in Bangkok

Inferno: Flames burn after the explosion in central Bangkok which is thought to have killed at least 21 people, including four foreigners

Target: A general view taken from a moving train shows the scene at the Erawan Shrine where the bomb exploded off a motorbike

Thailand's defence minister also said the bombing was aimed at foreigners in an attempt to damage the country's tourist industry, which is a rare bright spot in an otherwise gloomy economy.

Another government spokesman echoed the minister's comments, saying: 'The people who did it targeted foreigners and to damage tourism and the economy.'

Victims were 'blown to pieces' in the explosion, according to witnesses.

Mr Poompummuang added: 'Those who have planted this bomb are cruel. They aim to kill because everyone knows that at 7pm the shrine is crowded with Thais and foreigners. Planting a bomb there means they want to see a lot of dead people.'

Harrowing: This footage, taken from a dashcam of a vehicle, shows the moment the bomb exploded at the Erawan shrine in Bangkok

Explosion: The dashcam footage shows the dramatic moment the bomb exploded at the Hindu shrine which was packed with tourists

Devastating: A casualty is loaded into an ambulance on a stretcher (left) while officials try to determine the exact location of the bomb

Injured: A casualty is taken to the Police General Hospital in Bangkok as officials warn more than 120 people were injured in the explosion

Investigations: Thai police and bomb squad officers comb the scene of the explosion which has killed at least 21

Combing for evidence: Thai officials try to collect as much from the scene as possible as they try to establish who was behind the attack

Ongoing investigation: Bright forensic lights are installed at the crime scene as officials begin to work through the night at the bomb site

Patiently waiting: Two female tourists sit alongside Thai officers in the aftermath of the explosion as they come to terms with the blast

Bringing in the troops: Army officers could be seen patrolling the buildings around the shrine tonight as they searched for more devices

A witness at the scene said she saw pieces of human flesh near the blast site, and a soldier later told onlookers to move back, saying they were checking for a second bomb.

Those who have planted this bomb are cruel. They aim to kill because everyone knows that at 7pm the shrine is crowded with Thais and foreigners Police Chief Somyot Poompummuang

'We are now looking for another two to three bombs, as we have found one suspicious object,' Prawut Thawornsiri told Reuters.

'There could be another explosion, so we have blocked off the crime scene and are asking bystanders to move back.'

Bomb disposal squads later said they had found and defused a further two explosive devices that were discovered at the scene.

Authorities have since stepped up security checks at some major city intersections and in tourist areas.

Panupan Chansing, 20, a hotel worker at the nearby Grand Hyatt Erawan, said she heard a 'very loud' bang before running outside to discover the carnage.

She said 'The whole building began to shake so I ran outside to see what had happened.

'I saw bodies lying on the ground and I saw vehicles on fire. I feel very sad and sorry that this has happened to Thai people... I'm scared.'

Agony: A devastated woman cries out as crowds gathered searching for missing relatives in the wake of the devastating attack today

Upsetting: Thailand's Defense Minister said the bomb was designed to 'destroy the economy and tourism' of the country and that attackers deliberately targeted tourists

Carnage: Thai police officers inspect the scene of the explosion near Erawan Shrine, central Bangkok, after it occurred at 7pm local time

Site: Government bosses say as many as 21 people are feared dead and dozens more have been injured after the motorbike bomb today

Chaotic: Police have revealed that the explosion was the result of a bomb on a motorbike. A Thai soldier is pictured surveying the damage

Debris: Members of different emergency response teams and law enforcement officials inspect the scene after the explosion earlier today

Probe: Police confirmed the explosion, near a shrine at a major Bangkok road, was from a bomb but no one has yet claimed responsibility

Terror attack: A policeman walks past bodies covered in white sheets around the Erawan Shrine. Most of the injured were tourists from China and Taiwan, local media said

The Erawan shrine, on a busy corner near top hotels, shopping centres and offices, is a major tourist attraction, especially for visitors from East Asia

Pim Niyomwan, an English instructor working on the eighth floor of the building right next to the shrine, added: 'Suddenly there was a big boom, and the whole room just shook, like someone dropped a wrecking ball on top of our ceiling. The whole building just shook. My four students were hysterical.'

WHAT IS THE ERAWAN SHRINE? The shrine was built in 1956 in an attempt to ward off bad luck that was befalling the construction of the old Erawan Hotel

A Brahmin priest was consulted after a series of unfortunate events delayed construction including construction workers getting injured and the sinking of a ship carrying marble for the hotel

He suggested a shrine be built with a statue of Hindu god Brahma and as soon as it was erected the accidents stopped, according to Lonely Planet

Despite the original hotel being demolished in 1987, the shrine remains and is popular with locals who are seeking good fortune

It was vandalised in 2006 by a man with a mental illness who was then beaten to death by angry locals

Two months later it was replaced by a replica with hundreds attending its unveiling despite rain Advertisement

Richard Sri-kureja was walking to a shopping centre next to the shrine when he heard the huge explosion.

He said: 'There was total chaos. About five minutes later police and ambulances rushed to the scene. I counted around 20. That area is usually very crowded as it's in the middle of the city. A local hotel is full of injured patients.'

British tourist Tamar Johnson, 20, was in a hotel bar when she heard the blast and initially thought it was a crack of thunder.

She told the BBC: 'Then my mum phoned me from the hotel. She was shouting about a bomb so we sprinted back to our hotel.

'It was chaos – people were running around and there were police and ambulances everywhere. We got back and met up with Mum and Dad – obviously it was a huge relief to see them again.'

Briton Lucinda-Jane Chastain added to Sky News: 'It was just this massive explosive noise. The whole building shook. All we can see is a horrible mess on the road.'

Holger Siegle, a German who said he and his newlywed wife had chosen Thailand as their honeymoon destination because it seemed safe, also spoke of his shock.

'We didn't think anything like this could happen in Bangkok,' he said. 'Our honeymoon and our vacation will go on, but with a very unsafe feeling.'

Michael Williams, a 69-year-old Briton who regularly visits the country, suggested that politics could be the motive for the attack.

He said: 'It saddens me a lot because the Thais are beautiful people and they're tearing themselves apart for no particular reason at all.

'It won't stop me coming to Thailand, but I'm sure it will damage the Thai economy because people are scared to go anywhere,' he said, as he stood outside a hotel close to a police cordon.

'People will definitely think twice about coming to Thailand now,' he added.

Distress: Police had to hold back crowds as people gathered near the scene. Extra security checks are taking place at major tourist spots

Upset: A tearful woman is led away from the scene in a wheelchair as crowds start to gather near the scene in the hours after the attack

Investigation: Officials closed off an intersection after the explosion which shook the centre of Bangkok during the evening rush hour

Sealed off: Thai soldiers and police stand guard after a bomb exploded outside a religious shrine in central Bangkok

Flames: Crowds fled from the scene in the immediate aftermath of the blast. This scene was captured by local Mongkol Nunthalikitkun

'IT SOUNDED LIKE THUNDER': BRITISH TOURISTS WERE 'MOMENTS AWAY' FROM DEADLY BANGKOK EXPLOSION Terrified British tourists have described how they were in 'absolute hysterics' as a bomb ripped through one of Bangkok's most popular tourist spots today. British tourist Tamar Johnson, 20, was staying at the Holiday Inn on Silon Road Bangkok, and was just moments away from the explosion. She said: 'Me and my sister were in the sky bar at the Lebua Hotel when we heard a huge explosion. At first we thought it was just thunder because there's been electrical storms all day so we didn't think much of it. 'Then my mum phoned me from the hotel. She was in absolute hysterics shouting about a bomb so we sprinted back to our hotel. It was chaos, people were running around and there were police and ambulances everywhere. 'I'm almost certain we heard another explosion when we were running back. It's terrifying.' Tamar and her sister Phoebe, 17, both from Birmingham, are now back in the hotel with their family and have been told not to leave under any circumstances until the situation calms down. Tamar said: 'We got back and met up with Mum and Dad -obviously it was a huge relief to see them again. Now we're on the 23rd floor and we're all together waiting for it to calm down. It's really scary. The hotel staff are looking after us but they've closed the doors and told us not to leave until we hear anything else.' Briton Lucinda-Jane Chastain told Sky News how the whole building she was in shook blast happened. She said: 'It was just this massive explosive noise. The whole building shook. We all ran to the windows. It was quite hard to see what was happening but we could see debris in the street. 'All we can see is a horrible mess on the road. It's the last place in the world you'd expect something like this to happen.' Advertisement

Howard Fenton, a 50-year-old computer programmer from Australia, said he was dismayed to see violence return once more to Bangkok's streets.

'There's just been so many problems in Thailand over the years,' he told AFP.

'You sort of hope that it's going to go away but when it comes back again it's pretty shocking. And coming this violently is a real worry.

'I really hope sense will prevail and it doesn't spiral into something really, really shocking.'

The British Foreign Office this afternoon tweeted a link to its travel guidance for Thailand, writing: 'Explosion in central #Bangkok. There are reports of casualties. Monitor media and take extra care.'

The attack also drew quick expressions of grief from around the world, with UN Secretary-General Ban Ki-moon's office releasing a statement saying he was shocked.

'He expresses his condolences to the bereaved families and to the people and government of Thailand,' the statement said.

'He hopes that those responsible will be brought to justice.'

The US government also released a statement warning its citizens to avoid the area, while also voicing sympathy for the victims.

Police investigate the scene after the explosion. A spokesman said they were hunting two or three more devices

Images captured by Mongkol Nunthalikitkun shortly after the explosion show flames burning next to a motorbike lying on the road

Explosive Ordnance Disposal officers enter the Erawan Shrine. The tourist hotspot is on a busy corner near top hotels, shopping centres, offices and a hospital

Blood is seen near a victim's shoe, as security forces and emergency workers gather at the scene of the blast. The government is due to set up a 'war room' to coordinate the response to the blast

A number of burnt out motorbikes could be seen lying on the ground close to the shrine as police stepped up their investigations

Ambulance crews descended on the scene and treated dozens of people for injuries after the powerful blast near the shrine

The Erawan shrine, on a busy corner near top hotels, shopping centres and offices, is a major tourist attraction, especially for visitors from East Asia. Many ordinary Thais also worship there.

It sits at the foot of the five-star Grand Hyatt Erawan hotel and is surrounded by a string of large hotels and malls that draw tens of thousands of visitors each day.

In the hours after the attack, the normally thronging skywalk connecting those shopping centres was virtually abandoned while the streets below filled with police officers and soldiers manning checkpoints.

The Erawan is an enormously popular shrine to the Hindu god Brahma but is visited by thousands of Buddhist devotees every day. It is particularly popular with Chinese visitors, who travel to Thailand in larger numbers than any other nationality.

Soon after the blasts, the country's tourism minister Kobkarn Wattanavrangkul visited the nearby Chulalongkorn Hospital where many of the Chinese victims were taken.

'We wanted to make sure there are translators... because a lot of the Chinese they cannot speak English,' she said, adding that Chinese speaking volunteers had also turned up at the hospital to help out.

Asked whether the bombs would impact tourism she said: 'This is a big concern for us.'

Thai forces are fighting a low-level Muslim insurgency in the predominantly Buddhist country's south, although those rebels have rarely launched attacks outside their ethnic Malay heartland.

'The perpetrators intended to destroy the economy and tourism because the incident occurred in the heart of the tourism district,' Defense Minister Prawit Wongsuwan told Reuters.

Police used sniffer dogs as they scoured the scene for further explosive devices in the wake of the devastating bomb blast

A member of the bomb squad was seen walking in a protective suit as investigations got underway this evening

Thailand has been riven for a decade by an intense and sometimes violent struggle for power between political factions in Bangkok

Police Chief Somyot Poompummuang said the explosives were stuffed inside a tube and then wrapped with a white cloth before being detonated

The Erawan shrine, on a busy corner near top hotels, shopping centres, offices and a hospital, is a major tourist attraction, especially for visitors from East Asia (file picture)

While initial suspicion might fall on Muslim separatists in the south, Thailand has been riven for a decade by an intense and sometimes violent struggle for power between political factions in Bangkok.

Occasional small blasts have been blamed on one side or the other. Two pipe bombs exploded outside a luxury shopping mall in the same area in February, but caused little damage.

Police said that attack was aimed at raising tension when the city was under martial law. The army has ruled Thailand since May 2014, when it ousted an elected government after months of at times violent anti-government protests.

The shrine intersection was the site of months of anti-government protests in 2010 by supporters of ousted former Prime Minister Thaksin Shinawatra. Dozens were killed in a military crackdown and a shopping centre was set ablaze.

Islamic militants have carried out many attacks in other parts of Southeast Asia, including on Indonesia's holiday island of Bali in 2002 that killed 202 people. But they have not made Thailand a prime target.

A government spokesman said it was too early to speculate on who was behind the attack.

The blast came just hours after fresh economic data showed Thailand's economy had slowed in the second quarter, hit by weak domestic demand and exports.

Tourism, which accounts for 10 percent of the country's GDP, was one of the few positive growth areas.

Earlier this month the Tourism Authority of Thailand said arrivals were at 12.4 million in the first five months of this year, a 25 percent increase on the same period last year when Bangkok was wracked by street protests that eventually led a military coup.