QUETTA, Pakistan — Separatist militants killed at least 39 people in "coordinated" attacks in southwestern Pakistan on Monday that largely targeted ethnic Punjabis, government officials said.

In one of the attacks, dozens of militants stopped vehicles traveling on a highway through Balochistan province 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 Agence France-Presse (AFP).

Government officials have reported deadly attacks in at least three districts in impoverished Balochistan, where security forces are battling sectarian, ethnic and separatist violence.

"We have confirmed 39 people killed in several coordinated attacks carried out by the BLA terrorists," Shahid Rind, a spokesman for the Balochistan provincial government, told AFP.

In Musakhail district, between 30 and 40 gunmen stopped 22 buses, vans and trucks one after the other on a highway connecting Punjab with Balochistan, senior official Najibullah Kakar told AFP.

"Vehicles traveling to and from Punjab were inspected, and individuals from Punjab were identified and shot," he said.

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, said Javed Baloch, a senior government official in the district.

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

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

Prime Minister Shehbaz Sharif expressed "deep grief and condemnation over the terrorist attack" in a statement issued by his office on Monday.

In separate statements, Pakistani President Asif Ali Zardari and Interior Minister Mohsin Naqvi called the attack in Musakhail "barbaric" and vowed that those who were behind it would not escape justice. Naqvi also condemned the killings in Qalat.

Surge in violence

Balochistan is Pakistan's poorest province, despite an abundance of untapped natural resources, and lags behind the rest of the South Asian country in education, employment and economic development.

Baloch separatists have, in recent years, intensified attacks on Pakistanis from neighboring provinces working in the region, as well as foreign energy firms they believe are exploiting its riches.

Punjabis are the largest of the six main ethnic groups in Pakistan, and are perceived as dominating the ranks of the military, which is locked in a battle to quash Balochistan's armed factions.

The BLA mostly targets security forces, and attacks on civilians often go unclaimed.

In an attack in April, 11 Punjabi laborers were killed when they were abducted from a bus in the city of Naushki, and six Punjabis working as barbers were shot in May.

In February, on the eve of national elections, twin blasts in Balochistan killed 28 people and were claimed by the local chapter of the Islamic State group.

Protests led by ethnic Baloch are staged regularly in the province, accusing the authorities of a heavy-handed crackdown in their fight against militancy, including through mass arrests and detentions.

Pakistan has witnessed a surge in militant attacks since the Taliban returned to power in neighboring Afghanistan in 2021, mostly in the northwestern border province of Khyber Pakhtunkhwa, but also in Balochistan, which abuts Afghanistan and Iran.

There were at least 170 militant attacks killing 151 civilians and 114 security personnel in Balochistan last year, the Pakistan Institute for Conflict and Security Studies said.