The Pakistani army said ten soldiers were slain "during intense exchange of fire" while defending against a raid on a post in the Kech district of Balochistan overnight from Tuesday into Wednesday.

One assailant was killed and several others were injured by army troops, the statement said, adding a "clearance operation" underway to "hunt down perpetrators" had captured three gunmen.

In a statement to AFP, separatist group the Balochistan Liberation Army (BLA) claimed responsibility for the assault and said the military death toll stood at 17.

"The enemy's weapons and other military equipment were seized and the post was set on fire," the statement said, confirming one of their own militants was killed in the clash.

A spokesman for Pakistani Prime Minister Imran Khan said he felt "deep sorrow" over the incident.

"Every drop of blood of the soldiers guarantees the security of the country," his office said in a statement.

Last week another separatist group from the region, the Baloch Nationalist Army (BNA), carried out a bombing in the eastern city of Lahore, killing three people.

Separatists have been waging an insurgency for years in Balochistan, the largest but least populous province of Pakistan, which borders Iran.

It is the poorest region of the country but is rich in minerals, and resentment among residents has been stoked by billions of dollars of Chinese money flowing in through Beijing's Belt and Road Initiative.

Locals say the gargantuan international infrastructure project gives them few benefits, with employment awarded to outsiders.

The mountainous district of Kech is just north of the port of Gwadar -- the crown jewel of China's investment scheme in Pakistan.

Last April a suicide blast at a luxury hotel hosting the Chinese ambassador in Quetta, the provincial capital of Balochistan, killed four and wounded dozens. The ambassador was unhurt.