Gunmen have shot and killed three workers at a coal mine in south western Pakistan, officials say.
No one has immediately claimed responsibility for the attack.
Suhail Anwar Hashmi, the top administrator in Harnai district in Baluchistan province, said the early Sunday morning violence took place in the Sharag area where most of the province's coal mines are located.
Haranai is located about 200km north east of Quetta, the provincial capital of Baluchistan. Hashmi said counterterrorism and local police teams were searching for the assailants.
Baluch separatist groups have previously claimed responsibility for similar attacks on coal miners in the region.
The gas- and mineral-rich Baluchistan province has been the scene of a low-level insurgency for some two decades.
Initially, insurgents demanded a greater share for the local population of the province's gas and mineral income. But later, Baluch separatist groups started pressing for independence from Pakistan.
In January, gunmen abducted a group of workers from a coal mine in the district of Bolan and shot them dead in a nearby mountainous area.
Authorities found 11 bodies and three wounded at the site. The Islamic State group, which considers Shi'ites heretics, later claimed responsibility for the killings.