Martin McGuinness, an I.R.A. Leader Turned Peacemaker, Dies at 66

Martin McGuinness, a former Irish Republican Army commander and Sinn Fein political leader who helped negotiate peace in Northern Ireland after decades of sectarian violence, and became a senior official in its power-sharing government, has died in Derry. He was 66.

Sinn Fein said on its website on Tuesday that Mr. McGuinness had died during the night. When he resigned from the Belfast government in January, The Irish Times reported that he had amyloidosis, a rare condition caused by the a...