Police were called to the Donard Park area shortly before 7.30pm on Sunday, when two windows of a parked car were smashed.
A 38-year-old man was held on suspicion of criminal damage and drugs offences.
A 36-year-old woman was detained on suspicion of disorderly behaviour and assault on police.
Houses in Donacloney's Williams Street were evacuated when police raided a home in the area as part of follow-up searches.
A deactivated gun, drugs paraphernalia, and fireworks were uncovered during the operation.
Army bomb experts were also at the scene.
The man and woman are in custody helping police with their inquiries.