A warehouse caught fire after an explosion at the US Army Sagami depot (photo:Reuters)

(VOVworld) - An explosion rocked a warehouse at a US military base Monday in Sagamihara, Japan, 40 km southwest of Tokyo. The local fire department said the building that exploded was storing canisters of compressed air, nitrogen, oxygen and Freon. The fire was extinguished seven hours after the explosion. The Pentagon confirmed the explosion and there were no reports of injuries. The cause of the fire was not immediately known.