
Scotland Yard have issued an appeal to track down four men they consider to have been ringleaders in last night's London riots as officers face having their holiday leave cancelled amid fears violent summer clashes will continue.

Thousands more officers will be out on the beat tonight and across the weekend as the Met seeks to avoid repeats of Tuesday's chaos when violent scenes broke out in three parts of London.

An officer and two members of the public were knifed and four other PCs injured after a water fight and party in Hyde Park spiralled out of control in the city's worst bout of violence since the 2011 riots.

Two 16-year-old boys were stabbed at a separate water fight in Burgess Park, Southwark, while police attempting to shut down an illegal block party in Stamford Hill, Hackney, had bottles thrown at them.

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A Metropolitan Police officer and two members of the public were knifed and four other PCs were injured after a water fight and party in Hyde Park, central London, spiraled out of control yesterday (Pictured: Police in riot gear face a group of young people at the park)

A police officer in riot gear speaks to four young people after last night's water fight descended into chaos, with several injured

When police tried to shut down the event in Hyde Park and began seizing sound systems objects were hurled their direction

A police officer was stabbed and four other PCs were injured after the water fight and party in Hyde Park spiralled out of control

In response, last minute holiday requests will be vetoed by police chiefs desperate to up their numbers across the city in the hope of quelling any similar incidents.

The Met today revealed CCTV and photographic stills of four men they want to talk to in relation to last night's Hyde Park violence, during which police had glass bottles rained down on them.

They include four men sought over the scenes in the park and one for an alleged incident at Marble Arch.

Sharing their pictures online, Westminster MPS tweeted: 'We need to ID these men re incident in #HydePark Call 0208 785 8244 if you have any info or witnessed the disorder.'

The Met today revealed CCTV and photographic stills of four men they want to talk to in relation to last night's Hyde Park violence, during which police had glass bottles rained down on them

Also included in the police handout images are these two men. The man in the left image is wanted in connection with the scenes in Hyde Park. The man on the right is a person of interest in relation to an alleged incident at Marble Arch

Grainy footage has emerged of a young man, who has not been named, apparently being set upon by three others in the middle of a busy road near Hyde Park as buses, taxis and cars are forced to swerve around the attack.

In the footage, which was posted on social media, a youth wearing a white t-shirt appears to repeatedly thrust a weapon at another young man, who is on the floor grappling with two attackers, before all three run off as onlookers scream in horror.

Tempers flared as police tried to disperse the 4,000-strong crowd and began seizing sound equipment as a minority chanted 'Black Lives Matter'.

Meanwhile, two 16-year-old boys were stabbed at another pre-arranged water fight in Burgess Park, Southwark, last night while a nearby supermarket was ransacked by a group of 200 people. Neither of the injured boys suffered life-threatening injuries, although one remains in hospital.

And a block party on the Stamford Estate in Hackney also turned violent, as officers were pelted with missiles.

One terrified onlooker wrote on Facebook: 'I can't believe what I witnessed in Marble Arch whilst passing by on the bus.

'Young boys running around with large machete looking knifes, a whole leap of 16, 17, 18 year old girls & boys literally scattered everywhere, I was scared for all their lives.

'And what really shook me up was seeing the young black boy looked about 17 outside Hyde park with a stab wound to his chest.

'It was so heartbreaking, I called the ambulance from the bus as it literally just happened & just to make sure but no way was I getting off that bus it was so erratic buses had to stop, I saw police & no ambulance.'

Grainy footage has emerged of the young man, who has not been named, apparently being set upon by three others - one armed with a machete - in the middle of a busy road in central London

In the footage a youth wearing a white t-shirt (pictured left) appears to thrust a weapon at another young man (centre), who is on the floor grappling with two attackers, before all three run off. Police have said no arrests have been made so far

Now, the Metropolitan Police has announced it has launched an investigation into the disorder which was apparently sparked after officers prevented members of the crowd from setting up a sound system.

Hundreds of people have taken to social media to condemn the youths for using the Black Lives Matter slogan while carrying out mindless acts of violence. Police confirmed the event was not linked to the movement.

Shortly after 3pm yesterday afternoon hundreds of teenagers gathered - it is believed they were pupils from two different schools and the water fight had been pre-arranged, but the numbers continued to swell throughout the day and into the evening.

When police eventually tried to disperse the crowd shortly before 9pm, they were met with a 'hostile' reception.

A splatter of blood (pictured bottom left) is seen near the entrance to Hyde Park at Marble Arch in central London this morning

Police (pictured at Hyde Park today) have launched an investigation into last night's events after five officers were injured

Forensic officers were at the scene in Hyde Park today where a water fight descended into violence and three stabbings last night

Objects began to be hurled their direction and one officer was struck with what is believed to be a glass bottle and had to be taken to hospital for treatment.

More violent scenes then erupted - with another constable being stabbed and two members of the public also suffering knife wounds as crowds chanted 'Black Lives Matter'.

The police officers are both described as having 'non life-threatening injuries'.

There has been no update available on the condition of the two others who were also stabbed.

Unconfirmed reports on social media indicate all of the events were pre-arranged but poorly organised. The event in Hyde Park had been called 'Bashment in the Park' and a flyer had been circulating on Twitter and Facebook for a couple of days.

Thousands of revellers descended on the central London park to soak up the hottest day of the year. But shortly after 3pm yesterday afternoon, hundreds of teenagers are believed to have gathered for an impromptu water fight

The numbers continued to swell throughout the day and when police eventually tried to disperse the crowd shortly before 9pm, they were met with a 'hostile' reception

Hundreds of officers and riot police were sent to the popular London park to try and quell the chaotic scenes

The policemen are both described as having 'non life-threatening injuries'. There has as yet been no update available on the condition of the two others stabbed

Officers manage to push the crowds back towards Marble Arch, where a small group stormed a nearby branch of McDonald's.

BOTTLES THROWN AT POLICE AS THEY TRIED TO SHUT DOWN AN ILLEGAL BLOCK PARTY IN HACKNEY Meanwhile, a squad of elite police officers was pelted with missiles as they moved hundreds of revellers from an illegal block party in north London. Footage appeared to show scores of people running from the scene as officers from the Metropolitan Police's Territorial Support Group interrupted the unlicensed event and confiscated the sound system. Some officers suffered minor injuries as the crowd threw bottles and other items. Scotland Yard said some police vehicles were also damaged. Large crowds had gathered on the Stamford Hill Estate in Hackney on Tuesday evening as the capital enjoyed the hottest day of the year. Adverts for the block party had circulated on social media in the days before the event and Scotland Yard spoke to organisers. But the party went ahead with revellers arriving at 6pm. Advertisement

Terrified staff were forced to flee as teens leaped over the fast food chain's counters and stole food from the racks.

Commander Harrington said that the violence was not in any way related to the Black Lives Matter protests, adding: 'I've personally been involved in overseeing a Black Lives Matter protest in London, which has been wholly peaceful.

'Last night was not about Black Lives Matters, that may have been chanted in places, but that's not what this was about.

'This was about a group of people, who were committing violent acts of disorder against officers and members of the public.'

Asked whether racial tensions between certain communities and the police fuelled the violence, he said: 'We will look at all the angles. There is nothing at this stage to suggest that this was the case.

'This was not billed as a Black Lives Matter event. All the other events over the last two weeks, we've had positive feedback.'

'All I can be really clear about is that this is not a Black Lives Matter protest.'

He added: 'Our officers took action to step in and protect the public and themselves after the crowd attempted to set up a sound system.

'Concerned for the potential safety implications officers stepped in to negotiate with them. At that stage our officers came under attack, resulting in one suffering stab wounds and another who suffered a head injury. In total five officers were injured.

'Significantly, two of the officers who went in to negotiate the removal of the sound system, one was stabbed in the hand - what with, we don't know - the other was hit in the head with a glass bottle and sustained injuries.

'We're really pleased that they are both out of hospital. They didn't come to work to have that kind of injury. They were trying to keep the public safe.

'There were a number of injuries to members of the public. I haven't got the full details, but I know that they were hospitalised, it's not life-threatening.

'We will be speaking to those people to identify the attackers and prosecute them if we can.'

Two police officers have been rushed to hospital after being struck by a bottle and stabbed when they tried to disperse a huge water fight in Hyde Park

Objects began to be hurled their direction and one officer was struck and had to be taken to hospital for treatment

Riot control officers are seen standing armed with heavy duty shields and masked helmets

Dozens of police cars and vans raced to the scene after news broke of the riots unfolding in Hyde Park

He added: 'We are now running a post event investigation - I know that there is a lot of footage available, including helicopter footage and CCTV. If you have any footage that may help, or any information, then please get in touch with us.

'What took place wasn't a group of people out enjoying the sunshine, but crime and disorder which is quite simply unacceptable. Officers are out and about on duty today and we want everyone in London to have a safe and enjoyable day.

'If people are going to go along to unlicensed or spontaneous events then please think very carefully, they are simply not safe. You do not have the protection of attending a well organised and safe event.

'Parents and guardians are urged to think carefully about whether these sorts of events are where you want you children to go.'

Video footage from the scene shows youths running towards officers as a number of objects are launched through the air, with witnesses describing the scene as being 'like a war zone'.

A police helicopter was scrambled to monitor the violence after the 'riots' broke out near the Serpentine Lake shortly after 8.30pm.

Scotland Yard confirmed that the policeman hit by the bottle suffered an injury to his head.

Describing the madness on Twitter, one user said: 'Oh my life I nearly got stampeded.' Timi Marcel tweeted: 'Hyde Park is a bit of a war zone.'

Video footage from the scene shows youths running towards officers as a number of objects are launched through the air

Scotland Yard confirmed that the policeman hit by the bottle suffered an injury to his head and is in hospital

Any witnesses or anyone with information regarding last night's events is asked to call police in Westminster via 101

Members of the gathered crowd sprint through the park as tensions mount between the youths and the police

The meet-ups usually involve revellers dancing to loud music.

However, when police arrived to disperse members of the group the tone is thought to have changed.

Online, one woman wrote that fighting broke out because of 'boredom and stupidity', while other eye-witnesses reported people running and screaming.

On Facebook, Adisa Sesay, added: 'I can't believe what I witnessed in Marble Arch whilst passing by on the bus.

'Young boys running around with large machete looking knifes, a whole leap of 16, 17, 18 year old girls & boys literally scattered everywhere, I was scared for all their lives.

Online, one woman wrote that fighting broke out because of 'boredom and stupidity', while other eye-witnesses reported people running and screaming

Video footage from the scene shows youths running towards officers as a number of objects are launched through the air, with witnesses describing the scene as being 'like a war zone'

A police helicopter was scrambled to monitor the violence after the 'riots' broke out near the Serpentine Lake shortly after 8.30pm

Police officers from Scotland Yard gathered between riot vans as they orchestrated a plan to help control the chaos

Police officers formed a line to stop any of the rioting youngsters from passing by as they finally manage to bring calm

Terrified staff were forced to flee as teens leaped over the counters at McDonald's and stole food from the racks fast food chain's Marble Arch store

Twitter users were quick to condemn those heard chanting 'Black Lives Matter' while the police came under attack

In Burgess Park, south London, two 16-year-old boys were knifed as disorder broke out among 500 to 600 young people taking part in an end-of-term water fight in the sun, while a nearby supermarket was ransacked.

There was further disorder well into the night when police were pelted with missiles as they moved hundreds of revellers from an illegal block party in north-east London.

And a 15-year-old girl was taken to hospital on Monday evening with suspected knife wounds to the head after hundreds gathered for a street party in St Mary's Road, Harlesden, north-west London, police said.

Two women, aged 31 and 35, were arrested on suspicion of GBH at a nearby flat and taken to a north London police station.

The violent outbursts come as Britain swelters in a heatwave, with Tuesday's temperatures soaring to 33.5C (92.3F) in Brize Norton, Oxfordshire, on the hottest day of the year so far.

Met Police Commander BJ Harrington said: 'The people of London this morning are waking up to what is unacceptable criminal violence.'

The two 16-year-olds who were stabbed in Burgess Park suffered non life-threatening injuries, and one remains in hospital.

At around 8pm police were called to a supermarket in Dunton Road, Southwark, to reports of 200 people causing damage inside the store and stealing, with two female customers suffering minor injuries.

Detective Chief Superintendent Simon Messinger, borough commander for Southwark, said: "While at this stage we do not believe the events at Burgess Park to be linked to disorder elsewhere in London last night, clearly there are similarities with incidents quickly breaking out amongst a large group of youths."

Elsewhere, footage appeared to show scores of people running from the scene as officers from the Metropolitan Police's Territorial Support Group interrupted an unlicensed music event on the Stamford Hill Estate in Hackney.

Some officers suffered minor injuries as the crowd threw bottles and other items, and three police vans were damaged.

Mr Harrington said police would not tolerate violent behaviour and will be looking into whether any of the incidents were linked.

Extra officers will be on duty on Wednesday night across London and throughout the weekend.

Any witnesses to the Hyde Park disorder are asked to contact the incident room on 020 8246 0076 or contact Crimestoppers anonymously on 0800 555111, or police on 101.

As night descended, more and more police officers were required to attend the park as the hundreds-strong group failed to disperse

The National Police Air Service, the helicopter arm of the Met Police, posted on Twitter: 'Apologies to those disturbed on this beautiful evening, assisting @metpoliceuk and @mettaskforce with a public incident in Hyde Park'