Iraqi security forces say a large explosion demolished a building in the southern city of Basra. At least three militants were killed and four were wounded.
British military spokesman Maj. Tom Holloway says it's not clear what caused Monday's blast but insists no British, U.S. or Iraqi forces were involved.
But an Iraqi police official and witnesses say the building was destroyed in an air strike. They say those killed were gunmen using the abandoned house as a base.
The official spoke on condition of anonymity because he was not authorized to release the information.