Three men and a woman were today being questioned about a weapons seizure in Belfast.
Residents were evacuated from their homes overnight as military experts examined the scene at Burmah Street in the south of the city.
Soldiers were called in after police searches in the Ormeau Road area uncovered a number of guns.
Four arrests were made during the operation last night.
Homeowners were instructed to leave surrounding houses as the area was sealed off, but after the Army left police confirmed that all those evacuated had been allowed to return.