Updated, 8:19am

A SECOND MAN has been arrested in connection with the murder of Denis Donaldson almost five years ago.

The second man, aged in his 30s, was arrested late last night and is currently being detained at Letterkenny Garda Station.

Both he and the first arrested man, who is 70, are being held at Letterkenny Garda Station under Section 30 of the Offences Against The State Act.

Donaldson was murdered in April 2006 at his home in the rural area of Cloghercor near Doochary in Co Donegal.

Donaldson had been a senior figure within Sinn Féin and a volunteer for the Provisional IRA, but in 2005 was exposed by Gerry Adams as having spied for MI5 and for the Police Service of Northern Ireland.

He had previously served time in the Maze Prison in the 1970s and had been friendly with leading republican Bobby Sands, and had run for election to the House of Commons as a Sinn Féin candidate in 1983. He later became the administrator of Sinn Féin’s group in the Stormont Assembly.

The Real IRA later claimed responsibility for the murder. An inquest into Donaldson’s death, originally set for February, has been adjourned five times so as to allow a Garda investigation to continue.