Gardaí have arrested a second man, aged in his 30s, in connection with the murder of former Sinn Féin official Denis Donaldson.

No one has ever been charged with his murder but last night gardaí in Donegal arrested two men, both of them from the county.

Mr Donaldson, who admitted being a British agent for more than 20 years, was shot dead near Doochary, Co Donegal, in April 2006.

He was the former head of Sinn Féin's office at Stormont and had been living in Donegal since his admission that he had spied for the British.

The arrested men were taken to Letterkenny Garda Station for questioning under Section 30 of the Offences Against the State Act and can be held for an initial period of 24 hours, after which a Chief Superintendent can apply for an extension.

The first man arrested is 69 years old and from Dungloe. He had been living in Glasgow.

He was arrested on suspicion of withholding information.

The second man arrested is 31 and from Annagry. He was arrested on suspicion of possessing a firearm on the day Mr Donaldson was murdered.

An inquest into the death of Mr Donaldson was opened and adjourned a number of times since his death, most recently in February, when gardaí told the coroner that they were actively pursuing new avenues in the murder investigation and a further adjournment was granted.