The building collapse that killed five killed and injured one on Monday was not caused by the latest quake in northwest China's Qinghai Province, a safety administration official said Tuesday.

The accident happened at around 4 p.m. at Jinyuan Cement Factory in Donghe Town of Huzhu Tu Autonomous County in Haidong prefecture, more than 700 km away from the epicenter of Monday's 6.3-magnitude quake.

Workers were lifting a girder to its place with a crane for the factory's new workshop, when the girder hit another and caused a chain reaction which led to the collapse of 12 others in total.

The accident was a production safety accident and was not directly related to the earthquake, said a safety administrator from the Haidong prefecture government, citing initial investigation results.

Three of the victims were already dead when rescuers found them in the debris. Two others died during a rescue attempt, said Jin Shenghui, general manager of the Zhengping Group Co., which runs the cement plant.

The only victim still alive is being treated at the People's Hospital in the provincial capital of Xining. He is still in critical condition but "might still survive", Jin said, quoting a doctor.

A Xinhua reporter later saw at the scene two cranes parked among 12 collapsed girders on the construction site, with several safety helmets scattered around.

Yang Fenglin, the official in charge of safety production in the Department of Construction of Qinghai Province, said further investigation of the cause of the accident is still going on.

The provincial seismic network monitored more than 550 aftershocks after the Monday quake as of Tuesday morning, the largest measured 4.4 on the Richter scale.

The quake and aftershocks cracked walls of some houses near the epicenter in Da Qaidam, but no widespread damage has been reported.

The only injuries, so far, were three mine workers who were slightly hurt while being evacuated.

(Xinhua News Agency November 12, 2008)