BEIJING, June 22 -- Chinese President Xi Jinping on Thursday demanded all-out rescue and treatment of the injured and enhanced safety overhaul after a barbecue restaurant explosion in northwest China's Ningxia Hui Autonomous Region.

Xi, also general secretary of the Communist Party of China Central Committee and chairman of the Central Military Commission, made the instruction following the accident, urging more efforts to ensure the safety of the people's lives and property.

The explosion which ripped through a barbecue restaurant in Yinchuan, capital of Ningxia, on Wednesday night has left 31 dead and seven injured, local authorities said Thursday, which marks the start of the three-day Dragon Boat Festival holiday.

Xi urged efforts to ascertain the cause of the accident as soon as possible and hold the relevant people accountable in accordance with the law.

All regions and related departments should screen for and rectify all types of risks and hidden dangers, Xi noted.

Relevant departments should launch a campaign to promote workplace safety at an early date and enhance safety overhaul of key sectors and industries, Xi added.

Under Xi's instruction, a work group composed of several central government organs has been sent to the scene to guide the rescue efforts.

The cause of the accident is under investigation.