POLICE investigating the murder of a prison officer in the North have arrested two men.
Father of two David Black, 52, was shot dead as he drove to work on the M1 motorway in Co Armagh earlier this month.
Four men have already been arrested and released in connection with Mr Black's murder.
The latest suspects, aged 34 and 42, were detained in Coalisland, Co Tyrone.
Mr Black, from Cookstown, Co Tyrone, was gunned down in a high-speed motorway ambush as he drove to start his shift at Maghaberry prison in Co Antrim.
The long-serving officer was nearing retirement.
A dissident republican group styling itself as the "IRA" claimed the murder.
The two arrested men have been taken to the PSNI’s serious crime suite in Antrim.