A man is due in court in Dublin in relation to the investigation into the murder of Denis Donaldson.
Former Sinn Fein official Mr Donaldson was shot dead in Co Donegal in 2006, months after admitting his role as a police and MI5 agent over 20 years.
In 2009, the dissident republican group the Real IRA claimed responsibility for Mr Donaldson’s killing.
On Monday, Gardai investigating Mr Donaldson’s murder arrested a man aged late 40s following his extradition from Scotland on foot of a European Arrest Warrant.
The man is to appear before the Special Criminal Court on Monday afternoon.
The arrest was carried out with the assistance of An Garda Siochana Extradition Unit, Garda National Bureau of Investigation and the Irish Air Corps.
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