Tribal clashes killed at least 11 people in northwestern Pakistan on Saturday and injured eight, including women and children, a local official said.

Tensions rose in Kurram district, Khyber Pakhtunkhwa province, after two people were critically injured in a shooting incident between rival tribes. It wasn't immediately clear what caused the shooting.

Vehicles were targeted in different areas of the district, leading to more casualties, said senior official Javedullah Khan.

Khan said efforts were being made to secure travel routes and restore normalcy. The injured were taken to a hospital.

Pir Haider Ali Shah, a former parliamentarian and member of a tribal council, said elders had arrived in Kurram to mediate a peace agreement between the tribes.

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“The recent firing incidents are regrettable and have hampered efforts for lasting peace,” he said.

Last month, at least 25 people were killed in days of clashes between armed Shiites and Sunni Muslims over a land dispute. Although both live together largely peacefully in the country, tensions have existed for decades between them in some areas, especially in Kurram, where Shiites dominate in parts of the district.

Also Saturday, a separatist group in the southwest claimed responsibility for an attack that killed 21 people.

The Baloch Liberation Army said its fighters targeted a coal mine in Duki district with heavy weapons, rocket launchers and grenades late Thursday night.

It gave higher casualty figures of 30 dead and 18 injured. It also said that Pakistani security personnel were disguised as workers, without giving evidence.

It threatened more assaults unless the military withdrew from the province.

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Balochistan is home to several groups that demand independence from the federal government, accusing it of exploiting the oil- and mineral-rich province at the expense of locals.