Militants attacked a Pakistan naval airbase in the turbulent southwest region killing at least one paramilitary soldier while security forces killed all five of the assailants in retaliatory fire, officials said on Tuesday.

Monday's attack on the Turbat base was the second assault by ethnic Baloch militants on a military facility in the past week.

"We escaped a huge loss," said a statement from Prime Minister Shehbaz Sharif's office.

A Pakistan Navy spokesman said all five attackers were killed after they tried to break into the base.

One paramilitary soldier was also killed, said a military statement.

The Baloch Liberation Army (BLA), the most prominent of several separatist groups in Balochistan, claimed responsibility for the assault in a statement.

The BLA has previously been involved in attacks on Pakistani and Chinese interests in the region and elsewhere.

China has invested heavily in the mineral-rich southwestern province of Balochistan, which borders Afghanistan and Iran, including developing the port of Gwadar, despite a decades-long separatist insurgency.

The naval base is significant to the China-Pakistan Economic Corridor that also encompasses roads and energy projects and is part of Chinese President Xi Jinping's Belt and Road Initiative.

Pakistani security forces said last week they repulsed a gun and bomb attack by the BLA militants on a complex outside Gwadar, which in which two soldiers and all eight militants were killed.

Ethnic Baloch separatists have long claimed their communities are not getting a fair share of wealth from the region, which sits atop huge reserves of natural resources.

They have frequently targeted Pakistani security forces protecting foreign investment projects. (Agencies)