Interior minister of the province, Sarfaraz Bugti, said the militants had killed 20 kidnapped passengers after security forces chased them in the hilly area and exchanged fire with them.
According to the reports, the incident took place when unknown militants stopped two buses and kidnapped 35 passengers in the Khadd Koocha area of Mastung district of the province.
Soon after the incident, security forces rushed to the site and chased the kidnappers.
Bugti said the security forces have rescued six of the abducted passengers and are following the militants to rescue the remaining.
Deputy commissioner of the Mastung district said around 15-20 militants riding on vehicles kidnapped 35 passengers from two buses after identifying them.
The passenger buses were heading from provincial capital of Quetta to the countrys southern port city of Karachi.
Pakistani Prime Minister Nawaz Sharif condemned the incident and directed the authorities to rescue the remaining passengers safely.
No group has claimed responsibility for the incident yet.
Editor: Ade P Marboen
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