Three labourers were killed and another injured when suspected militants opened fire on them in Balochistan's Harnai district on Tuesday evening, Levies officials said.

The firing incident took place in Naks area of Harnai district, the officials said, adding that the victims were repairing the railway track in Harnai when they were targeted by the miscreants.

As a result of firing, three labourers died on the spot while the injured was rushed to District Headquarter Hospital (DHQ) Harnai for emergency medical treatment.

Initial reports suggested that the victims belonged to Balochistan's Zob district. The miscreants escaped unhurt after the firing.

Levies and Frontier Corps personnel rushed to the spot and initiated an investigation into the firing incident.

The incident comes weeks after the cold-blooded murder of 15 labourers in Balochistan's Kech district.