More than a dozen people were reported to have died on Saturday following the leak from a refrigeration unit at a cold storage facility in Shanghai's northern district of Baoshan.

According to Xinhua, the incident occurred at 10:50 a.m. local time (02:50 GMT) at Shanghai Weng's Cold Storage Industrial Co. Ltd. It did not give any further details.

Six of the 26 people injured remain in a critical condition, news agency Reuters has reported, citing government sources.

The cause of the leak remains unknown.

China has a poor record on workplace safety and industrial accidents are common.

In June, 120 people died and dozens more were injured following a fire at a chicken processing plant in China's northeastern Jilin province.

ccp/tj (AFP, AP, Reuters)