Among those three is Wu Chi-tao, the chairman of Kunshan Zhongrong Metal Products, the company that operated the factory in Zhoushan, roughly 80 miles west of Shanghai. The company's general manager and the manager in charge of workplace safety joined Chi-tao in custody, China's state news agency, Xinhua, told Reuters.
Previous reports indicated that five of the company's executives were already in custody following the blast, although it's unclear if Chi-tao and the other two managers were counted in that total.
The blast at the factory, which polishes wheel hubs for General Motors China, killed 75 people and has injured 185, and is currently being blamed on illegal production methods and poor safety facilities. PRC President Xi Jingping has since issued a nationwide crackdown on factory safety in response to the disaster.