At least 23 people were killed after two coal mines collapsed in Pakistan’s Balochistan province on Saturday, The Tribune reported. Several people are trapped inside, rescue officials said. They added that the toll is likely to increase.

In the first incident, 16 miners died in a collapse in Marwaarh, near Balochistan’s capital Quetta. “The roof caved in following an explosion triggered by the accumulation of methane gas, killing 16 miners and wounding nine others, two of them seriously”, Jawaid Shahwani, commissioner of Quetta Division told Geo News. There were 30 workers inside the mine at the time of the accident.

“We are trying our best to recover bodies but it will take time as most of them are buried very deep,” Shahwani said.

In the second mine collapse, seven miners were killed in Sooranj area, also near Quetta. Two unconscious workers were rescued and bodies of two miners were recovered on Saturday night. Five bodies were recovered on Sunday, when the rescue operation resumed.