QUETTA: Unidentified men destroyed four power transmission towers between Balochistan's areas of Sibbi and Machh on Monday.

The attack led to a reduction of 100 MW of electricity which was to be supplied to parts of the southwestern province.

The reduction moreover led to an increase in the duration of load-shedding in 15 districts of the province.

A spokesman for the Quetta Electricity Supply Company (Qesco) said repair work on the towers would be initiated once the company received security clearance in this regard.

No one claimed responsibility for the attack.

Impoverished Balochistan, which borders Iran and Afghanistan, has been wracked by an insurgency waged by ethnic Baloch tribes seeking more political rights and a greater share of profits from the region's natural resources.

Hundreds of people have died in violence ripping through the province since the insurgency flared in late 2004.

The region has also been hit by attacks blamed on Taliban militants, although sabotage of gas pipelines and power transmission lines are a trademark of separatist militants.