Sixteen people were killed over a decades-long land dispute between two tribes in Pakistan’s coal-rich northwest, police said Tuesday.

The Akhorwal tribe opened fire on the Suni Khel tribe from an elevated position on Monday, police said, as the latter marked the boundaries of their territory in the mountainous area of Darra Adam Khel, less than 100 kilometres (60 miles) from the Afghan border.

“The tribes were equipped with powerful firearms, and within a matter of minutes, the violent clash had resulted in a significant number of casualties,” Farhan Khan, a senior police official, told AFP.

Khan said the clash followed several previous jirgas – tribal councils of elders responsible for settling disputes – that had failed to yield any resolution.

“The clash left 12 individuals from the Suni Khel tribe and four individuals from the Akhorwal tribe dead, while an additional four people sustained injuries,” local police spokesman Fazal Naeem told AFP.

Inter-family feuds are common in Pakistan, but in the mountainous northwestern region – where communities abide by traditional tribal honour codes – they can be particularly protracted and violent.

Darra Adam Khel is a part of the Kohat district of Khyber Pakhtunkhwa province, home to the largest coal reserves in the region, with disputes over deposits common between tribes.

Despite safety concerns and a lack of regulatory oversight, mining is a vital source of employment and income for the local community.

The police said that since the shooting, the situation in the area had been brought under control with the involvement of a local jirga.

Darra Adam Khel is part of the former Federally Administered Tribal Areas (FATA), a semi-autonomous region in northwestern Pakistan that was merged with Khyber Pakhtunkhwa province in 2018, bringing it into the legal and administrative mainstream.