Nationalists and loyalists clashed during eight hours of rioting in Belfast, police said yesterday.
The violence erupted in Cluan Place and Clandeboye Gardens in the east of the city around 6pm on Saturday.
Police have yet to establish a motive for the trouble but it is thought it may have been sparked by the Rangers v Celtic match in Glasgow on Saturday afternoon.
Bottles, bricks and bolts were thrown. One person was taken to hospital with a head injury but no gunshot wounds were reported.
Around 1.30am yesterday the British army was called to deal with a suspected blast bomb in Clandeboye Gardens.
Experts made safe the device and removed it for examination.
As they left the scene, police vehicles were attacked with bricks and one man was arrested for disorderly behaviour.
Calm was restored to the area around 2.30am with the help of community representatives. - PA