The number of people confirmed killed in a huge landslide last month in China has risen to 58, authorities said Wednesday, with several more still missing.

The landslide in the southern city of Shenzhen, which was caused by the improper storage of waste from construction sites, was the latest in a series of fatal man-made accidents in the world's most populous country.

Initially only seven people were declared dead with scores missing, but Shenzhen authorities said on a verified social media account that a total of 58 bodies had been recovered by Wednesday, and efforts were continuing.

The updated toll implied that at least 25 people were still missing.

Soil was illegally piled 100 metres (330 feet) high at an old quarry site and turned to mud in heavy rain on December 20, according to earlier Chinese media reports.

More than 10,600 rescuers and nearly 2,200 heavy machines have been mobilised in the rescue efforts and more than two million cubic metres of earth were moved, Shenzhen authorities said.

China is prone to accidents linked to lax industrial safety enforcement.

A coal mine collapse in the northern province of Shanxi on Wednesday trapped 11 miners, weeks after a gypsum mine in Shandong province in the east caved in while 29 miners were working underground, with only 11 escaping or being rescued so far.

In August, chemical blasts in the northern port city of Tianjin killed almost 200 people, in one of the most deadly industrial accidents to hit the country in recent years.