An explosion at the entrance to a kindergarten in eastern China has left at least seven people dead and 60 injured, with early photos purportedly from the scene showing bloodied children and adults lying on the ground. Reuters reports state media did not say if children are among the dead. The blast reportedly struck around 4:50 p.m. Thursday in the city of Xuzhou, 375 miles northeast of Shanghai, the official Xinhua news agency reported. The cause of the blast is unclear, and domestic officials said a gas container accident could be the source. Beijing maintains a tight control over the country’s firearms, and most previous terror attacks have used knives, axes, or homemade explosives. Kindergartens are sometimes targeted in revenge attacks, the AP reports.