Six people have been injured and more than 150 houses were damaged in an explosion that occurred at a fireworks factory in southwest Sichuan Province Tuesday morning, Xinhua quoted a county official as saying. The explosion occurred at 7 a.m. in the Huima Township Fireworks Factory in Daying County in the city of Suining, and a fire triggered by the explosion was put out by 10 a.m., said Liu Hui, deputy county head. Three people suffered severe injuries and three others sustained minor injuries in the explosion, Liu said. The operation of the factory was suspended on Monday. The blast occurred while 10 workers were cleaning at the site, he said. Residences near the explosion site had their windows shattered by the shockwave of the blast. The cause of the explosion is under investigation.