A 33-year-old man arrested over the murder of Jim Donegan outside a west Belfast school last year has been released unconditionally.
Police said the man was arrested this morning under the Terrorism Act. He was released several hours later.
Mr Donegan (43) was shot dead outside St Mary's Grammar School on the Glen Road on December 4 as he sat in his Porsche waiting to collect his 13-year-old son.
Several people have been arrested in connection with the murder but so far no one has been charged.
In February, the Police Ombudsman confirmed it had launched an investigation into how the PSNI dealt with information about a potential threat to Mr Donegan.