At least two people died and 30 were injured by an explosion in Ningbo in east China's Zhejiang province on Sunday. The explosion occurred at about 9am local time (1am GMT) and shattered windows around a kilometer away from the blast site, according to local media. The blast occurred at the site of a demolished factory and affected many nearby residential areas, Xinhua reports citing local police. The cause of the explosion is unclear so far and an investigation is underway.