Sinn Fein's Martin McGuinness, a former deputy first minister of Northern Ireland and IRA commander who was a key figure in Irish politics for five decades, has died at 66, prompting tributes from allies and enemies alike.

Ireland's state broadcaster RTE reported his death on Tuesday and said that he had died at Derry's Altnagelvin Hospital with his family by his side.

The face of Irish Republicanism for many during three decades of violence that killed more than 3,600 people, McGuinness remained a figure of hate for many pro-British Protestants until his death.

But he earned widespread respect across Britain and Ireland by embracing his bitterest rivals to cement a peace deal in 1998 that allowed Northern Ireland to slowly return to normality.

As a young Irish Republican Army (IRA) fighter, he saw his mission as defending the Catholic minority against the largely pro-British Protestants who for decades dominated Northern Ireland.

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For his critics, that cause was never enough to justify the IRA's lengthy armed campaign for the northern province, which is part of the United Kingdom, to be united with the independent Republic of Ireland in the south.

In 1973 he was convicted by the Irish Republic's courts of being an IRA member after being stopped in a car packed with explosives and bullets and was briefly jailed.

He went on, though, to serve as deputy first minister in a power-sharing government in Northern Ireland. Key to its success was his close relationship with Ian Paisley, a firebrand preacher many Catholics see as a key player in the genesis of the conflict.

A partnership many thought would prove impossible was soon dubbed by the media "the Chuckle Brothers" and allowed McGuinness to become Northern Ireland's deputy first minister in 2007.

"Martin McGuinness, certainly when I was growing up, was the godfather of the IRA and he was a man who struck terror quite literally into the hearts and into the lives of many, many people and that moved of course from being the godfather to being the man in government and that remarkable journey is something that is incredibly important," Paisley's son, Ian Paisley Junior, also a leading politician, said.

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"As a Christian, as someone who reflects on life, it's not how you start your life that is important, but how you finish your life."

McGuinness was hailed as a peacemaker for negotiating the 1998 peace deal, sharing power with his once bitter enemy Paisley and shaking hands with the British Queen, though the gestures were condemned by some former comrades as treachery.

Unlike his close Belfast associate, Sinn Fein president Gerry Adams, McGuinness was always open about the fact that he had been a senior leader of the IRA - classed as a "terrorist organisation" by the British government.

"Martin McGuinness never went to war, it came to his streets, it came to his city, it came to his community," Adams told RTE on Tuesday. "He was a great man in my opinion and he will be missed."

McGuinness appeared unmasked at early IRA press conferences, and the BBC filmed him walking through his native Bogside area of Derry discussing how its command structure worked.

During one of his two Dublin trials for IRA membership, he declared from the dock he was "a member of the Derry Brigade of the IRA and I'm very, very proud of it."

Tony Blair, who was British prime minister during the process that led to the 1998 agreement, said he had come to know a man that had decided to set aside armed struggle to seek peace.

"There will be some who cannot forget the bitter legacy of the war," Blair said. "And for those who lost loved ones in it that is completely understandable. But for those of us able finally to bring about the Northern Ireland peace agreement, we know we could never have done it without Martin's leadership, courage and quiet insistence that the past should not define the future."

Ireland's president, Michael D Higgins, praised his commitment to democracy and said his leadership would be missed in both Northern Ireland and the Republic.

"As President of Ireland, I wish to pay tribute to his immense contribution to the advancement of peace and reconciliation in Northern Ireland - a contribution which has rightly been recognised across all shades of opinion," he said in a statement.

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Britain's Prime Minister Theresa May said in a statement: "While I can never condone the path he took in the earlier part of his life ... he made an essential and historic contribution to the extraordinary journey of Northern Ireland from conflict to peace."

McGuinness was forced to step down in January, a number of months before a planned retirement, because of an undisclosed illness. Irish media reported he was suffering from a rare heart condition.

At the time, frail and emotional, he told a large group of supporters gathered outside his home in the Bogside area of Northern Ireland's second city that it broke his heart that he had to bow out of politics.

"I don't really care how history assesses me, but I'm very proud of where I've come from," he told RTE.

He is survived by his wife, Bernadette, and four children.



