A 33-year-old man has been charged with murdering prison officer David Black, who was gunned down on a motorway in Northern Ireland as he travelled to work.
Dissident republicans opposed to the peace process were blamed for the attack on the M1 motorway in County Armagh in November 2012.
He was the 31st member of the prison service to be killed in Northern Ireland, the first such murder in almost 20 years.
The suspect, who was detained yesterday in the Lurgan area of Co Armagh, is to appear in court in Craigavon later today.
A PSNI spokeswoman said the force wanted to thank Irish police for their help and support throughout a "difficult and complex" investigation spanning both sides of the border.
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