Los Angeles, May 17 (IANS) Eleven firefighters were injured in an explosion inside a building in Los Angeles, authorities said.The Los Angeles Fire Department (LAFD) tweeted that the blaze inside the one-story commercial building was reported at 6.26 p.m. on Saturday, reports Xinhua news agency."As firefighters were making their entry in and finding the seat of the fire, there was a significant explosion," LAFD Captain Erik Scott told a news briefing.The explosion caused fires at several buildings."Over 230 firefighters are responding. Firefighters have moved to a defensive posture for fire attack, and a medical branch has been created for treating and transporting injured firefighters," the LAFD said in a fire update later.TV footage showed raging flames raging and black smoke billowing out of building.Officials said that three of the injured firefighters were in critical, but not life-threatening, condition.The business at the building, called Smoke Tokes Warehouse Distributor, is "a supplier for those who make butane honey oil", according to officials.The cause of the fire is under investigation. --IANS ksk/