BELFAST An Irish militant group opposed to Northern Ireland's 1998 peace deal claimed responsibility for the attempted murder of a prison officer in a bomb attack on Friday, in a statement to the BBC that warned of more attacks.
The prison officer was seriously injured by a bomb which exploded under his van in Belfast. Police said there was a "severe" threat to security forces as the centenary approaches of the 1916 anti-British Easter Rising.
The attack was claimed by a group known as the new IRA, one of a number of small militant groups opposed to a 1998 peace deal that largely ended three decades of violence in Northern Ireland between Protestants, who want to remain under British rule, and Catholics favouring unification with Ireland.
The group said in the statement that it targeted the 52-year-old father of two because he was responsible for the training of prison officers who work in a wing of the top security Maghaberry Prison in Co Antrim where there is a dispute between dissident inmates and the authorities.
Three men and a woman were arrested in a police operation on Sunday for questioning about the attempted murder and remained in custody on Monday, police said.
The new IRA group, an amalgamation in 2012 of a number of dissident republican groups opposed to a ceasefire by the Provisional Irish Republican Army, which was responsible for more than half of the 3,600 deaths in the Northern Ireland conflict in the three decades to 1998.
The new IRA was responsible for the 2012 murder of another prison officer, David Black, who was shot dead as he drove to work at the prison.
In the statement to the BBC in Belfast the dissident group said there would be more attacks on prison officers and "all aspects of the security forces".
A "significant" amount of bomb-making components and explosives were found at a country park north of Belfast, police said on Sunday.
(Additional reporting by Conor Humphries; Editing by Janet Lawrence)