PESHAWAR, Pakistan -- A methane gas explosion ripped through a coal mine in northwest Pakistan on Wednesday, killing nine miners and injuring four others, a government official said.
The explosion happened in a remote area in Orakzai, a district in the Khyber Pakhtunkhwa province bordering Afghanistan, said Mohammad Arif, an adviser for the Mines and Minerals Department.
Pakistan's Prime Minister Shahbaz Sharif and local government officials in separate statements expressed sorrow over the incident. Arif said officials were investigating to determine if there was negligence involved in the incident.
Safety standards are commonly ignored in the coal mining industry in Pakistan, leading to accidents and explosions that have killed numerous mine workers in recent years.