Chinese state media say an explosion in an illegal fireworks factory has killed 13 people and injured two. Saturday's blast flattened three rooms in a rented house in the eastern province of Shandong. The Xinhua News Agency said the blast shook the earth and damaged neighboring homes. Some residents mistook it for an earthquake. Xinhua said police were hunting for the house's tenant. Neighbors did not know that the house was being used to make fireworks, Associated Press reported.