Dublin, Ireland ? Joe Cahill, a founding father of the modern Irish Republican Army who once narrowly avoided the hangman’s noose, has died, the IRA-linked Sinn Fein party announced Saturday. He was 84.

Cahill died Friday in his Belfast home after suffering for years from asbestosis, a lung-ravaging condition he acquired while working in Belfast’s Harland & Wolff shipyards in the 1950s.

Cahill was the first Belfast commander of the modern “Provisional” wing of the IRA founded in December 1969, the year that Northern Ireland descended into decades of civil unrest.

He was also the principal mentor of Sinn Fein leader Gerry Adams, who, as an IRA member, served under Cahill’s direct command in the early 1970s, when the IRA began killing British soldiers and police and bombing towns and cities in Northern Ireland and England.

After killing about 1,800 people and maiming thousands, IRA commanders called open-ended cease-fires in 1994 and 1997 — when Cahill’s vote in favor was considered critical.

“Joe Cahill spent a lifetime in struggle. He was both a leader and a servant of the republican cause,” Adams said Saturday.

“He was an unapologetic physical-force republican who fought when he felt that was the only option. But he also significantly stood for peace and was a champion of the Sinn Fein peace strategy.”

Cahill, born in Belfast in 1920, was sentenced to death alongside five other IRA members for killing a policeman in 1942. While one of his colleagues, Tom Williams, was hanged, Cahill and the others had their sentences commuted to life. British authorities freed him in 1949.

Cahill remained in the old IRA through a 1956-62 campaign, but like many northern hard-liners broke from the Dublin-based organization when it failed to defend Catholic parts of Belfast adequately from Protestant mob violence in August 1969.

Cahill quickly rose through the ranks of the fledgling “Provos,” as the new IRA wing was nicknamed. He also traveled to the United States to help found Irish Northern Aid, the Provisional IRA’s fund-raising arm overseas.

In 1972 he became IRA chief of staff, the senior day-to-day command position, and moved to Dublin to avoid capture by British security forces.

He pioneered contacts with Libyan dictator Moammar Gadhafi and, in March 1973, was caught by the Irish navy as he tried to smuggle five tons of Russian-made explosives, rifles, pistols and ammunition from Libya.