A defenceless teenager lies bleeding at the water's edge during a brutal "happy slap" beating filmed by his cowardly assailants.

The youngster, thought to be no older than 16, is a victim of a sickening trend for filming attacks gaining credence among Brighton's teenage criminals.

Police were last night unable to identify the beach attackers but they have named two gangs which have taken part in a series of other attacks, posting their activities on the internet.

Police say their ringleaders include ten teenagers responsible for a THIRD of all violent attacks and robberies in central Brighton.

The group of thugs, including a teenage girl, are divided between two gangs responsible for terrorising shoppers and businesses in central Brighton.

Detectives say they are receiving daily calls from the public reporting the activities of the Yung Ofenderz and the IDC.

Problems with shoplifting, muggings, mobile phone theft, anti-gay hate crime and attacks on foreign students are so bad city police are planning a special task force to arrest the ring leaders.

They have also assigned patrols to public transport to combat a rise in yob behaviour on the top decks of buses.

The two main gangs even brag about their sickening behaviour on the internet and vile videos show the wannabe gangsters in action.

Films show the thugs : l Attacking innocent shoppers in Brighton city centre l Goading commuters at Hove station l Rampaging through a double-decker bus shouting obscenities.

The Argus launched its own investigation into the gangs.

When we contacted one of the people claiming to be a gang member he threw a tantrum and was heard screaming in the background while his mother spoke on the phone.

The teenager, Dean Thompson, 16, then sent a vile e-mail threat to The Argus.

His mother contacted the paper. She said her son was a member of the Yung Ofenderz but did not cause any trouble or commit crimes.

She said he had never been in trouble and was "picked on" by police. Within minutes of the call, a reporter received an email from Thompson.

It said: "Oi. You put my name in the paper you stupid bitch I'll go f****** mad you mug and plus I'm not allowed my name in paper. I'm too young silly cow."

Although Thompson brags of being a member of the gang there is no evidence he has been involved in any of the crimes police are investigating.

Inspector Laurence Taylor, of Sussex Police, has a bulging dossier on the groups.

He said: "We want to target the main offenders and get rid of those problems.

"There is a group of ten who are the biggest troublemakers. They seem to stir the others up.

"Most of them come from two groups who call themselves Yung Ofenderz and IDC. This list of ten are the priority."

The Yung Offenderz and the IDC - which stands for Independent Crew - gather in large groups in front of the Churchill Square shopping centre, on the seafront and at The Level.

Insp Taylor said: "We have had problems and we recognise we have a youth disorder problem.

"By hitting it hard in the beginning we stop it from becoming an issue."

Police say nine boys and one girl aged between 13 and 18 are ringleaders.

Many members of the gangs are not suspected of any crime but a hardcore suspected of carrying out serious assaults and robberies have so far avoided arrest because of a lack of evidence.

Insp Taylor said: "They are responsible for robberies and nasty assaults. It's generally antisocial behaviour but high level antisocial behaviour."

The crackdown will be run by a sergeant with two constables and four community support officers.

In a further effort to curtail the yobs, bus passengers will be able to use a confidential text service to report incidents as they are taking place. Passengers will be asked to provide details about the bus route and say if the behaviour is "hate" motivated.

Police officers will visit schools and colleges to encourage youngsters to behave themselves.

Insp Taylor said there have been occasions over the last five months where buses have been evacuated because of the behaviour of youngsters on board.

He said: "Bus drivers have refused to drive on until everybody has left the bus. We are working with the bus company to try and encourage drivers to report this behaviour."

To see our video report, click here.

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