A man has been arrested in connection with murder of Londonderry man Andrew Allen in 2012.
The arrest happened on Saturday night, according to An Garda Siochana, and centred on the fatal shooting on February 9 2012 in Links View Park, south of Buncrana, Co Donegal.
Mr Allen was said to have been one of a number of people who had been intimidated out of Londonderry city.
He was aged 24.
The man arrested at the weekend is aged in his early 50s.
He was arrested in the “Co Donegal area”, said Gardai.
He was being detained at Letterkenny Garda Station under Section 30 of the Offences Against the State Act, 1939 (as amended).
Gardai said in a statement that they wish to appeal for witnesses who may have been in the Links View Park area of Buncrana prior to or after the shooting and anyone who may have seen anything unusual or suspicious in the days leading up to the shooting.
Witnesses are asked to contact Buncrana Garda Station on 074-9320540, the Garda Confidential Telephone Line 1800 666 111, or any Garda Station.