Former IRA leader turned Garda agent Sean O’Callaghan died while on holiday in the Caribbean earlier this week.
The 62-year-old had been visiting a relative in Jamaica, reported Independent.ie website.
O’Callaghan, who described himself as the former head of the IRA’s ‘southern command’ penned an autobiography called The Informer: The True Life Story of One Man’s War on Terrorism.
According to Mr O’Callaghan’s autobiography he joined the Provisonal IRA in 1970 at the age of 15.
He resigned from the terrorist organisation in 1975, claiming to have been disillusioned with everything it stood for.
When he rejoined in 1979, he had volunteering his services to the Irish police as in informer.
He was jailed in the late eighties after he handed himself in to British police and admitted involvement in IRA activities in Northern Ireland in the mid-seventies.
He was sentenced to life imprisonment and released under Royal Prerogative in 1996.
In his autobiography he claims to have thwarted an number of IRA operations including a plan to assassinate Prince Charles and Princess Diana at a London theatre.
Writing in the Irish Times in January 1997, O’Callaghan said: “As a Kerry teenager, I joined the IRA and became a bomber, a robber and a double murderer. When I came to my senses and realised I was committing criminal acts for a vicious sectarian organisation I left, but my conscience drove me to rejoin in order to work against it.
“I served as an informer for the Irish government and in the course of six years I helped to stop a huge IRA arms shipment and I sabotaged many ‘violent and criminal plans’.”