Deputy First Minister Martin McGuinness had led tributes to a party member who died in a car crash.
Two men were killed when their blue BMW crashed and burst into flames on the Agivey Road area of Kilrea, Co Londonderry, at about 3.30am.
Mr McGuinness said the victims were Sinn Fein member Christopher O'Neill and his close friend Declan McKenna.
Mr O'Neill is the grandson of former party councillor John Davey, who was shot dead by loyalists in February 1989.
"Last night's accident outside Kilrea has claimed the lives of two young local men and I would extend my condolences to both families involved," said Mr McGuinness.
"Declan McKenna and Christopher O'Neill were close friends and died together last night in this tragic accident.
"Christopher O'Neill is the chairperson of the local Sinn Fein Cumann in Kilrea. Republicans in Co Derry and beyond are deeply shocked today at this terrible news.
"On behalf of Republicans throughout Ireland I would wish to extend my condolences to the families involved at this most difficult of times."
The PSNI are investigating the cause of the accident.
"The Agivey Road remains closed and police would ask anyone who may have seen the blue BMW M3 car in the Kilrea area in the hours preceding the collision to contact them in Coleraine," a spokesman added.