A series of documents released yesterday by the FBI shows that Sen. Edward Kennedy was subject of a serious threat sent from a group called the Ulster Defense group over his stance on Northern Ireland.

The over 2,000 pages of documentation released by the FBI range from death treats to obscenities from angry people to outright death threats.

The threats persisted even after Kennedy stopped becoming a serious candidate for Presidential election.

Some of the hate mail was in reaction to the Senator's involvement in the Northern Ireland issue throughout his career.

One such letter, from the 'Ulster Defense' group, said "the real murderers of Ulster are the American people who have paid money to support this insane situation".

The letter continued: "in return, every one of these bigoted Americans will pay with his own life. He [Kennedy] will pay for what he has done to Ulster, and he will pay with his own life!"

The FBI followed up the death threat and informed Irish and British intelligence. There is no report on whether the originator of the threat was ever located.

The Northern Irish death threat was one of many threats that the Senator received for his work on Northern Ireland. However, it seems to have been the most serious one.

The documents reveal that death threats were a part of life for Kennedy One such threat received after Kennedy had faded from the political spotlight read:"Brass tacks, I'm gonna kill Kennedy and Reagan and I really, really mean it".

A footnote at the bottom of the file page said: "Due to nature of the threats, consider subject armed and dangerous."

Another investigated incident involved one Michigan man reporting that he was approached by three people, one who had a money clip with $5,000, and asked him how much he wanted to kill the senator, according to the documents. The men were supposed to contact him the next day and never did.

One document told of how in 1977, a former California prison inmate told Arizona authorities that Sirhan Sirhan, the assassin of Robert Kennedy, offered him $1 million and a car to kill Edward Kennedy. The former inmate, who wasn’t identified, said he declined the offer.

Some of the threats were expertly analysed by experts in many fields. Psycholinguists worked in co-operation with senior FBI officials to piece together the often fractured psyches of the individuals making the threats. The file concluded that the person making the above threat was probably just an attention-seeker and most likely harmless.

Explicit threats were also directed against other members of the Kennedy family.

Many of the threats made against Kennedy were chillingly specific: "Ted Kennedy number three to be assassinated on October 25, 1968. The Kennedy residence must be well protected on that date”, read one such threat.

The threats came from far and wide: "These threats originated from multiple sources, including individuals, anonymous persons and members of radical groups such as the Ku Klux Klan, 'Minutemen' organizations and the National Socialist White People's Party.", said the FBI report.

President Kennedy was assassinated in Dallas on Nov. 22, 1963. Robert Kennedy was slain in Los Angeles on June 6, 1968, many of the letters chillingly and explicitly stated that Ted was going to be the third to go,.

Today’s release was highly anticipated by scholars, historians, and those interested in the Kennedys. The files offer a fascinating glimpse into the life and times of one of the world’s most famous political dynasties.

Ted Kennedy