Published Wednesday, 07 November 2012
David Black, who died in an ambush on the M1, on Thursday morning. (© Pacemaker)
The man has been taken to Antrim Serious Crime Suite for questioning.
Mr Black, a 52-year-old father-of-two from Cookstown, was ambushed by gunmen while driving to work at Maghaberry along the M1 near Lurgan on Thursday morning.
He was fatally shot after a dark blue Toyota Camry with Dublin-registered number plates pulled up alongside his black Audi A4.
Mr Black is the 30th prison officer to be murdered in Northern Ireland since 1974.
Two men aged 44 and 31, detained in the Lurgan area on Friday in connection with the murder were released unconditionally on Sunday.
A 29-year-old man arrested in Co Leitrim by Gardaí has also been released without charge on Monday.
Anyone with information about David Black's murder is asked to contact the special incident room at Lurgan PSNI station on 028 38 315291 or Crimestoppers on 0800 555 111.
© UTV News