Pakistani forces backed by helicopters killed at least nine separatists after the outlawed group abducted and executed an army officer, government and security officials said on Friday.
The military and local authorities confirmed on Thursday that up to 15 insurgents disguised as police killed Colonel Laeeq Mirza after abducting him on Tuesday when he was traveling with his family from the town of Ziarat, 60 miles (100 kilometres) northeast of Quetta, the capital of Balochistan.
The military did not share any updates about the operation on Friday.
Mirza had been was heading to a tourist resort when members of the outlawed Balochistan Liberation Army (BLA), designated a "terrorist" group by the United States in 2019, halted his vehicle on a highway and seized him.
The group later claimed that it executed Mirza – but let his family members live because they were not involved in crimes against the group.
Local government officials confirmed that the attackers freed the colonel's family members.
According to two security officials, the insurgents were surrounded near the area of Harnai and Manga dam, where an exchange of fire was still continuing.
They spoke on condition of anonymity because they were not authorised to speak to the media.
But the military said the colonel's civilian cousin – Umar Javed, who was traveling with him – was also abducted and remains in captivity.
The military said in a statement it was trying to find and rescue the hostage.
The killing of the colonel has drawn widespread condemnation in Pakistan.
President Arif Alvi and Prime Minister Shahbaz Sharif have vowed that those linked to the incident will be traced, arrested and punished.
For years, Balochistan has been the scene of a low-level insurgency by the BLA and other separatist groups demanding independence from the central government in Islamabad.
Although the government says it has quelled the insurgency, violence in the province has persisted.
In February, the separatist insurgents attacked two military facilities in Balochistan, killing at least nine soldiers.
In the subsequent exchange of fire, troops killed all the 20 assailants in the hours-long firefights and follow-up operations.
A female suicide bomber from BLA in April targeted a vehicle carrying Chinese teachers inside a university campus in the port city of Karachi, killing three Chinese nationals and their Pakistani driver.
Since then, Pakistan has arrested or killed dozens of members of the group in multiple raids in Balochistan.