Twelve people are reported dead and 12 injured after an explosion ripped through a railway tunnel under construction through a coal seam in southern China on 2 May.
Officials in Dafang County in Guizhou Province said those killed had been trapped inside the Qishanyan Tunnel after after the blast, reports news agency AP.
Methane gas from the coal seam is the suspected cause of the blast.
Rescue teams were hampered by high levels of carbon monoxide gas, and it took teams 14 hours to recover the victims, most of whom were workers, AP reported.
The rescue effort lasted until early on 3 May, said AP.
According to state news agency Xinhua the accident happened around 2:50pm in the Liulong Township of Dafang County.
A gas explosion is suspected as the Qishanyan Tunnel is designed to pass through a coal seam, a local government spokesman told Xinhua.
The exact cause of the accident is being investigated.
Image: Rescuers work at a tunnel blast site in Dafang County, China on 2 May 2017 (Xinhua)