The PSNI on Friday released one of two men arrested on Thursday by its terrorism investigation unit in connection with an investigation into alleged Continuity IRA activity.
The 37-year-old man arrested in Newtownabbey was released unconditionally, while a 31-year-old man arrested in west Belfast remained in police custody.
Police said that in searches in west Belfast and Newtownabbey on the outskirts of north Belfast they seized what they “suspected” was ammunition.
Detective Inspector Adrian Brown said a "number of searches were conducted in west Belfast and Newtownabbey on Thursday in connection with an ongoing investigation into violent dissident republican activity linked to the Continuity IRA".
“A number of items, including a quantity of suspected ammunition, have been seized for further examination,” he added.
The arrests and searches came in the wake of two suspected Continuity IRA attacks designed to kill police officers and British army bomb disposal members in the past five weeks in Craigavon, Co Armagh and near the Border in Co Fermanagh at Wattle Bridge.
In Craigavon on July 26th an attempt was made to lure police officers into a booby-trap bomb attack. The plan, which failed, was to cause an explosion with a secondary device while officers dealt with a hoax device.
On August 19th in a similar incident there was an explosion nearby while police officer and members of a bomb disposal team were dealing with another hoax device at Wattle Bridge near Newtownbutler.
No one was injured in that attack although the PSNI said it was clearly designed to kill.