LONDONDERRY, Northern Ireland (AP) — Northern Ireland police say a small bomb has detonated outside a probation office on a residential street in Londonderry, injuring nobody, and the city's leaders have accused IRA die-hards of recklessly endangering the lives of families living nearby.

The blast at Crawford Square damaged the unoccupied three-story office building after dark Monday. No group claimed responsibility, but police and politicians blamed Irish Republican Army members, who reject their side's 1997 cease-fire. Londonderry is a base for IRA factions opposed to Northern Ireland's peace process.

A politician representing the city's Irish nationalist majority, Colum Eastwood, says someone identifying himself as an IRA representative telephoned a suicide hotline warning of the bomb. Eastwood accused the caller of giving a deliberately short warning so that police had no time to evacuate local residents.