A security personnel stands guard near charred truck containers torched by armed separatist group at central Bolan district in Balochistan on Wednesday. AFP

Four Pakistan servicemen and two civilians were among 15 killed in an hours-long gun battle with Balochistan militants in the southwest of the country, the military said.

Provincial officials told the media on Tuesday at least six militants were killed in the clashes, but the military said later that "nine terrorists including three suicide bombers" had died in the exchange.

"However, during intense exchange of fire, four brave members of Law Enforcement Agencies, having fought gallantly, embraced Shahadat (martyrdom) along with two innocent civilians," said Inter-Services Public Relations (ISPR), the Pakistan military's information wing.

Caretaker Balochistan Information Minister Jan Achakzai initially attributed the attack to terrorists affiliated with the Aslam Acho group, but responsibility was later claimed by the Majeed Brigade of the proscribed Balochistan Liberation Army (BLA).

Security forces immediately responded to the attack and took up positions. The gun battle between terrorists and security forces had continued for several hours.

In a post on social media platform X, Achakzai said, "Updated missing persons list.”

The minister previously stated that missing persons are "BLA [banned Balochistan Liberation Army] terrorists.”

"We commend the swift action taken by the Pakistan Army and Frontier Constabulary Balochistan in thwarting a terrorist attack in Mach, Balochistan,” he said.

"Five BLA terrorists have been neutralised, ensuring the safety of our citizens,” he said, appreciating the "courage and dedication” of the armed forces.

In a separate post, he also shared a picture of one of the dead militants. "After the clearance operation in Mach, Balochistan, the dead body of a terrorist recovered. There are many more. So far reports, five terrorists were neutralised,” he said.

An AFP photographer saw the charred remains of several trucks in Bolan Colony, an arid district punctuated by fortified hills and scene of some of the heaviest fighting.

According to the police, at least 15 rockets were fired from nearby mountains, which landed and exploded in different areas of Mach on Monday night.

After firing rockets, terrorists attacked a camp of the security forces near the central jail and also entered the Mach railway station. There were reports that a railway policeman was martyred in the attack, while a truck driver was injured. However, no casualty was officially confirmed.

Soon after the attack, Mach town plunged into darkness and traffic on the Quetta-Sibi Highway was suspended.

Earlier, Achakzai said no damage was reported to any installations, nor were there any casualties among the security forces.

Achakzai’s remarks came after, according to officials, rockets landed and exploded near a camp of the security forces close to the Central Jail Mach, the prison’s residential area and other places in town.

Balochistan Inspector General Prisons Shuja Kasi confirmed that rockets hit the walls of the residential colony of the Mach jail.

"Mortar shells and rockets exploded close to the walls of the colony,” he said, adding that no report of any casualty was received so far.

The jail superintendent refuted social media reports that the gate and walls of the prison had been damaged. "Mach Jail and prisoners are completely safe and no rocket hit jail walls or premises,” he said.

The officer said that at present 800 prisoners were kept in Mach Jail, which included some death-row prisoners.

Officials said that armed men also attacked a police station in the Gokart area. However, levies and security forces immediately responded and thwarted it. A truck driver, Abdul Malik Shahwani was brought to the district hospital Dhadar with bullet injuries.