Gunmen shot and killed at least 39 people in "coordinated attacks" in southwest Pakistan on Monday.

In one of the attacks, dozens of militants stopped vehicles traveling on a highway through Balochistan province in the Musakhail district and shot 23 people dead – one of the worst shootings in the region in the past several years.

The Baloch Liberation Army (BLA), the most active militant separatist group in the province, claimed responsibility for an overnight operation in a statement sent to AFP.

Government officials have reported deadly attacks in at least three districts in impoverished Balochistan.

Najibullah Kakar, a senior official in Musakhail, told AFP that the militants stopped several buses, trucks, and vans on a highway linking Punjab with Balochistan.

"At least 22 people were killed and five injured when militants intercepted the vehicles," he said of the first attack, adding that passengers from Punjab were singled out and shot.

Among the victims were 19 Punjabis and three Baloch, mostly laborers from Punjab, according to Kakar. Hameed Zehri, another senior district official, confirmed the death toll and suggested that the Baloch Liberation Army (BLA), the region's most active militant separatist group, was likely responsible for the attack.

In its statement, the BLA said it had launched an operation "on highways across Balochistan", claiming to have targeted only security personnel.

An earlier statement from the group published just after midnight on Monday warned the Baloch public to stay away from the highways, adding that their "fight is against the occupying Pakistani military."

Militants also blew up a railway bridge in nearby Bolan district on a track that connects the province to Punjab and Sindh, with six dead bodies found nearby, according to Javed Baloch, a senior government official in the district.

Ten people,  including four paramilitary officers and one policeman responding to incidents, were also killed in Kalat district, provincial government spokesman Rind said.

Gunmen had stormed a hotel and also targeted a village elder with perceived links to the security forces, Nabi Baksh, from the Levies paramilitary force that works alongside the police, said.

In a similar attack last April, armed individuals in southwest Pakistan killed 11 people, including migrant laborers, in an attack believed to be carried out by separatist militants near Naushki in Balochistan Province. At the time, six gunmen intercepted a bus around 8:00 pm, checking passengers' ID cards and abducting nine workers from Punjab, local police stated. The bodies of the abducted workers were later discovered about two kilometers from the highway, having been shot at close range.

Despite being Pakistan's largest province, Balochistan remains its poorest, despite its wealth of untapped natural resources.

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