Gardaí investigating the murder of Denis Donaldson at his home at Cloghercor, Doochary, Co. Donegal in April 2006 have arrested a male aged in his 40s this evening in connection with the murder.
He is currently detained at Monaghan Garda Station under Section 30 of the Offences against the State Act, 1939.
This is the third arrest in relation to this ongoing investigation.
Donaldson, 56, was Sinn Féin's senior official at Stormont and a political enforcer for the party leadership. He was shot dead at a remote cottage in Doochary, Co Donegal, in April 2006.
Four months earlier, he had been expelled from the party after admitting that he had been a paid British spy for 20 years.
No one has ever been charged with his murder.
Donaldson was last seen by the Garda Siochaan, in Glenties on 3 April 2006, about 24 hours before he was murdered.
His body was discovered by a member of the public, who noticed his door open and called police. He had been shot twice, once in the head and once in the arm.