<div><span style="font-size: 1rem;"><b>Ten people have died and one remained trapped after the roof of a school gym collapsed in northeastern China, state media reported Monday.</b></span><br></div><div><br></div><div>The gym at the No. 34 Middle School in Qiqihar, Heilongjiang Province collapsed just before 3 pm (0700 GMT) on Sunday, state news agency Xinhua said.</div><div><br></div><div>As of 5:30 am Monday, 14 people had been pulled from the wreckage, state broadcaster CCTV said, "among whom four were pulled out without vital signs, and six died after treatment failed".</div><div><br></div><div>Footage aired by CCTV showed the entire roof collapsed onto the gym and rescue workers picking through the debris.</div><div><br></div><div>"A search and rescue operation involving nearly 160 firefighters and 39 fire trucks has been launched," CCTV said.</div><div><br></div><div>An initial investigation into the collapse found that construction workers had placed perlite -- a form of volcanic glass -- on the roof, Xinhua said.</div><div><br></div><div>Heavy rain then led the perlite to expand, causing the roof to collapse, it added.</div><div><br></div><div>"Those in charge of the construction company have been taken into police custody," the state news agency reported.</div><div><br></div><div>Industrial accidents are common in China due to lax safety standards and poor enforcement.</div><div><br></div><div>One of the worst such accidents took place in 2015 in Tianjin, where a gigantic explosion at a chemical warehouse killed at least 165 people. - AFP</div><div><br></div><div>bnbd24/fas</div>