Northern Ireland police say nine police officers were injured and 18 rioters arrested in the second straight night of violent protests over flying the British flag.
Police said Saturday that more than 30 petrol bombs were thrown at officers, along with ball bearings, fireworks and bricks as they responded to clashes Friday night in Protestant sections of Belfast.
Friday's clashes come a day after 10 police were injured in east Belfast during a similar demonstration.
Many Protestants want Belfast City Council to reverse a Dec. 3 decision to stop flying the British flag year-round, a move backed by Irish Catholics. Dozens of police have been injured in ensuing protests, and Protestant extremists have issued threats against politicians.