The murder of a senior Hell’s Angel has led to an explosion of violence between rival biker gangs as they battle to control criminal activities.

Seven members of the Outlaws gang will be sentenced today for the murder of Gerry Tobin, a “fully patched” Hell’s Angel, shot while riding his Harley-Davidson on the M40 as he returned from the Bulldog Bash biker festival in August last year.

Police believe that his killing has sparked an international battle and that his murder must have been authorised by the Outlaws’ leaders in the United States.

There are only 250 “fully patched” Hell’s Angels in Britain and 200 Outlaws entitled to wear the insignia. However, there are hundreds of affiliate members and thousands of middle-aged “weekend bikers” who buy the gangs’ merchandising and attend the profitable festivals.

Fears of further clashes between the gangs, who control drug networks and gun smuggling, led to police seeking the cancellation of several biker festivals across the country this year.

An application for a licence for this year’s Bulldog Bash, held by Hell’s Angels in Long Marston, Warwickshire, was opposed by William Holland, assistant chief constable of Warwickshire. “The clear evidence from this country and abroad is that the Hell’s Angels and the Outlaws are organised crime groups,” he said. “What we have evidence of is increasing tension between the Hell’s Angels and the Outlaws.”

The four-day festival was allowed to go ahead in August with no reports of violence. But police pressure forced the cancellation of the Ink and Iron tattoo show in Birmingham in April after tip-offs that it would be used as a showdown between the gangs.

The Rock and Blues Custom Show organised by the Outlaws in Derbyshire, the Welsh National Motorcycle Show and the Anglesey Bike Show were also cancelled because of police concern.

Mr Tobin’s murder was followed by international violence. Scandinavian authorities reported an attempt to blow up an Outlaws clubhouse where one individual was killed. In January Outlaws were ambushed by Hell’s Angels at Birmingham airport after arriving from Spain. Three men were seriously injured and one almost died.

Amid concern about the escalating violence police in Essex and Gloucestershire raided properties of known Outlaws, recovering shotguns, pistols and ammunition.

Each of the gangs’ chapters is an independent operation authorised by the headquarters in America, making it difficult for police to make a co-ordinated response.

Birmingham Crown Court was told that all the members of the South Warwickshire chapter of the Outlaws were involved in the murder of Mr Tobin, 35. He was killed in a “military-style operation” by a single shot fired from a car. In it were Sean Creighton, 44, the chapter’s president, Dane Garside, 42, vice-president, and Simon Turner, 41, “sergeant-at-arms”. Malcolm Bull, 53, the treasurer, was “spotter”, watching who was leaving the Bulldog Bash.

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