A rocket hit a house in Khairdin village, some 430 kilometers southeast of Quetta, the capital of restive Baluchistan province, early on Saturday morning, killing a couple and their four children.

"A man, a woman and their four children were killed when a rocket hit their house," senior police official Javed Shah said.

"Apparently the rocket was fired by miscreants," Shah said referring to tribal rebels who have waged an insurgency to demand more autonomy over region's natural resources like oil, gas and minerals.

"We are investigating the incident," he added.

Separately unknown gunmen intercepted three oil tankers carrying fuel destined for NATO forces in Afghanistan, setting one of them on fire and puncturing two others causing the oil to leak, Shah said.

The tankers were attacked in Bolan district, some 70 kilometers (40 miles) east of Quetta, but there were no casualties, he added.

Local security officials confirmed both incidents and toll.

NATO trucks and oil tankers are frequently targeted by arson attacks blamed on insurgents attempting to disrupt two key supply lines that cross western Pakistan bound for foreign troops fighting in neighbouring Afghanistan.

Most supplies and equipment for coalition troops in Afghanistan are shipped through Pakistan, although US troops are increasingly using alternative routes through central Asia.

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