Coal is a major source of energy in China, but its mines are among the world’s deadliest, largely due to lax enforcement of safety standards, despite repeated government orders for improvements in safety over the years.

Authorities ordered mines in several major mining regions to conduct safety inspections after the Alxa League accident.

On Thursday afternoon, more than a dozen bulldozers, trucks, SUVs and fire engines were seen passing through a remote police checkpoint about 25km south-west of the mine.

Nearly all personnel were stopped by police and checked for entry approvals before being allowed to proceed along the road leading to the mine.

A police officer said only those with government approval would be allowed access to the area. She said people living close to the mine had been sent to stay in a nearby town.

Security was also tight at another checkpoint in the neighbouring region of Ningxia, 15km east of the mine, with dozens of officers inspecting every vehicle that sought to pass in either direction.

Cranes and other pieces of heavy equipment could be seen, along with covered trucks. It was unclear what the trucks were carrying.

Rescuers used heavy digging equipment and cameras that could snake down into the debris, along with thermal imagers and equipment to detect vital signs, Chang Zhigang, the head of the rescue operation, told reporters.

Loading

Crews were using extreme caution to avoid more secondary disasters, Chang said.

“We will continue to increase the rescue force, race against time, and do our best to search and rescue the lives of every trapped person,” he said.

Police are investigating the cause of the collapse and some people have been detained, Chang said.

“We will publicise the result of the investigation in due course,” he said.

Reuters, AP

Our Breaking News Alert will notify you of significant breaking news when it happens. Get it here.