The death toll from a quarry blast at a south China cement factory earlier this week has risen to 10 while 18 other have been confirmed injured, local authorites have said.

The blast occurred on Monday afternoon at the Longshan Cement Company in Yingde, Guangdong province, Xinhua news agency reported. The blast has resulted in the death of eight of the company’s workers, a driver from an explosive sales company and a security guard, Liu Weirong, spokesperson of the Yingde municipal government said at a press briefing. Workers were unloading the explosives from the last of three trucks that transported the explosives to the quarry, according to Liu.

The explosives sales company is a licensed one that has supplied explosives to the Longshan Cement Company on a long-term basis, said Huang Jiwen, manager of the sales company.

Of the 18 injured, nine are workers from the cement company and the others are residents in the nearby town of Yinghong, which is separated from the quarry by a river, Liu said.

A probe into the cause of the blast is currently underway. The quarry belongs to the Longshan Cement Company which is owned by Taiwan Cement Company (TCC) International.