Janesville firefighters are looking for the cause of an early Thursday morning blaze outside Alter Recycling in the 1700 block of Beloit Avenue. Fire Shift Commander Scott Morovits says the call came in just after midnight. Damage was contained to the dumpster, which was inside a secured area. Morovits says firefighters were forced to cut the locks to get in the area. He says flames were shooting 15 feet into the air. Damage was contained to the dumpster.