A bomb planted in a parked van exploded outside a village police station, slightly injuring five policemen and nine civilians, police said today.

No one claimed responsibility for the explosion Thursday night but police said they suspected the Irish Republican Army. The mainly Catholic IRA recently has stepped up its campaign against authorities in the British province.A police spokesman said a warning was telephoned to police in the County Tyrone village of Coagh, a Protestant area 25 miles west of Belfast, shortly before the explosion. Police were evacuating residents from nearby houses when the bomb went off, the spokesman said.