Northern Ireland police say 40 officers have been injured during two nights of Catholic riots inspired by the mass parades of the province's Protestant majority.

A senior police commander, Alistair Finlay, says police have arrested 26 suspected rioters so far. Among them are several people who turned themselves in after suffering wounds that required hospitalization, including being struck by the police's blunt-nosed plastic bullets.

Finlay says officers suffered cuts and bruises, burns and whiplash. Violence regularly accompanies the annual July 12 parades by the Orange Order.

The Protestant brotherhood's parades themselves passed peacefully Tuesday, but several hundred Catholic youths attacked police both before and after the sectarian demonstrations.