Four men and a woman have been arrested in connection with dissident republican terror activities.
The men - aged 28 to 44 - were taken into custody in the greater Belfast area on Thursday night.
A 29-year-old woman was detained later, police said.
The suspects are being questioned by detectives from the police's serious crime squad in Antrim.
The arrests came as army bomb disposal experts made safe a viable explosive device in the university area of Belfast.
A number of homes were evacuated after the bomb was discovered in an alleyway off Eblana Street near Queen's University.
A controlled explosion was carried out on the device during the alert.