YINCHUAN, July 9 (Xinhuanet) -- Five workers were killed in a dam collapse accident in northwestern China's Ningxia Hui Autonomous Region Friday, according to the local police.

    The tragedy occurred at 11:40 a.m. Friday at a dam constructionsite in Guyuan, a city in southern Ningxia, leaving a 120-meter long, 100-meter wide, and 500-meter deep ditch, in which five workers were buried on the spot, said a witness.

    Local government officials and rescuers rushed to the spot for rescue after the accident happened. Bodies of the five workers were found two hours later.

    Preliminary investigation showed loosen earth is the main causeof the accident.

    Further investigation is underway. Enditem