The FBI is investigating the possibility that one of the world's most wanted mobsters is in Brighton.

Irish-American crime boss James "Whitey" Bulger, who is wanted for 18 murders, has been on the run for eight years.

Although Bulger was a leading gangland figure in Boston in the USA, there have been recent reports of him in England.

The FBI, working with Scotland Yard, found paperwork linking him to rented property in Brighton.

A spokesman for the Metropolitan Police said the investigation was now being handled by FBI agents, who were searching for more information on Bulger's links to Brighton.

Irish police found a safety deposit box belonging to Bulger at a bank in Dublin last September.

They were able to open it with a key found the previous week in a safety deposit box at a London bank.

A £1 million reward has been put up for the arrest of 73-year-old Bulger, who is listed as one of the FBI's ten most wanted fugitives.

Bulger, whose nickname comes from his shock of distinctive blond hair, spent nine years in prison during the Fifties and Sixties for bank robberies.

In the Seventies, he teamed up with veteran mobster Stephen Flemmi and rose through the ranks of the dominant Winter Hill Gang in Boston.

He gained a reputation as a ruthless enforcer and killer, specialising in drug trafficking and extortion.

In 1975, FBI agent John Connolly convinced Bulger to sign up as an informant, helping agents crack down on the Italian mafia.

In return, Connolly tipped him off about bugs and surveillance vehicles.

By the Eighties, Bulger and Flemmi were the undisputed kings of organised crime in Boston.

When Connolly retired, the FBI turned their attention to Bulger but he was prepared and started travelling the world with his girlfriend, Catherine Grieg.

They left money and false identification papers in safety deposit boxes.

They disappeared when federal racketeering and extortion charges were handed down against Bulger in 1995.

Connolly was jailed for ten years in September 2002 for offences linked to Bulger.

The FBI believes Bulger may be living in England posing as an American tourist, or hidden among one of Britain's Irish communities.

He has adopted a string of aliases, including Thomas F Baxter, Mark Shapeton, Tom Harris and Tom Marshall and has been known to disguise himself.

According to the FBI, he and Grieg love animals and may pay frequent visits to animal shelters.

He is also described as an avid reader with an interest in history.

A massive poster and publicity campaign is about to be launched worldwide to step up the search.

An FBI spokeswoman in Boston said: "We are keen to hear from anyone with information about Bulger's possible Brighton links."