BAGHDAD, April 07, SPA -- Iraqi security forces say a large explosion has demolished a building in the southern city of Basra,killing at least three militants and wounding four. British military spokesman Maj. Tom Holloway says it's notclear what caused Monday's blast but insists no British,U.S. or Iraqi forces were involved, the Associated Press reported. An Iraqi police official and witnesses say those killedwere gunmen using the abandoned house as a base, and thatthe building was destroyed in an air strike.--SPA www.spa.gov.sa/543718