A pro-government tribal elder and six members of his family were killed when unknown gunmen stormed their home in Dera Bugti early Tuesday, officials said.
The pre-dawn attack occurred in Dera Bugti district, some 450 kilometres southeast of Quetta, a hub for separatist rebels, Islamist insurgents and sectarian militants.
"Dodha Khan, his wife, son, daughter-in-law and three grandsons have been killed in the attack," Abdul Jabbar, a senior government official in Dera Bugti told AFP.
Jabbar said more than a dozen attackers armed with assault rifles and other sophisticated weapons came in vehicles and sprayed the family with bullets.
One female member of the family was struggling for her life in a local hospital where her condition was critical, Jabbar said, adding that attackers fled safely after the killing.
Officials said they were investigating whether Khan and his family members were killed because of his support for the government or whether he had some personal enmity with anyone.
Manzoor Ahmad, spokesman for the government paramilitary Frontier Corps confirmed the attack and the death toll.
No group has yet claimed responsibility but Baluch separatist groups have in the past killed local tribal elders for supporting the Pakistan government.
An insurgency pushing for political autonomy and a greater share of profits from the region's oil, gas and mineral resources began in the province in 2004.