PESHAWAR, Pakistan (AP) — Pakistani police said they found a mass grave on Friday containing the bodies of 16 coal miners who went missing in the country’s northwest a decade ago and were believed abducted by militants.

The miners went missing in 2011 while on their way to work at a mine in the district of Kohat, bout 75 kilometers (45 miles) south of Peshawar, the provincial capital of Khyber Pakhtunkhwa province bordering Afghanistan.

No one had claimed to have abducted the miners but militant groups were active in the area at the time.

Forensic experts carried out the exhumations after a villager in the remote mountainous area alerted them to what he assumed was a burial site, said police official Aleem Khan.

Family members of the victims were able to identify the bodies from the clothes and remains, Khan said, and the remains were handed over to the families for burial. The miners were from the town of Shangla in Swat Valley.

Khan said police would continue investigating the deaths to try to determine who killed the miners.

Although attacks on miners and other laborers are common in the southwestern Baluchistan province, such violence is rare elsewhere in Pakistan. Earlier this year in Baluchistan, militants from the Islamic State group abducted and killed 11 coal miners members of Pakistan’s minority Shiites.