There's been a powerful explosion at a factory in eastern China's Nanjing, capital of Jiangsu Province. Local officials told a press conference that at least 5 people have been killed.

An initial investigation shows a gas leak triggered the blast at around 10am on Wednesday in the plastics factory in a northern part of the city. Xinhua reporters have seen at least 6 people recorded dead as hospitals treat people injured in the blast. Local media says more than 300 people have been hospitalized, and at least 50 are seriously injured.

Buildings and vehicles within a 100 meter radius of the plant were seriously damaged. The explosion also hit a passing bus, injuring many passengers. The area has been sealed off. Fire-fighters have brought the blaze in the factory building under control. Rescuers are searching for people in the debris.