Bomb kills at least 12 on Pakistani bus

QUETTA, Pakistan, Feb 5 (Reuters) - A bomb exploded on a bus in southwest Pakistan on Sunday, killing at least 12 people and wounding 13, the latest incident in a spasm of violence to hit the troubled province of Baluchistan.

The explosion happened in a pass at Kolpur, about 60 km (40 miles) south of Quetta, the capital of Baluchistan, Interior Minister Aftab Ahmed Khan Sherpao told Reuters.

"It was a bomb explosion," he said. "This is a guess, but possibly they may have stored it in a bag and placed it under a seat. It happened at 5.30 p.m. (1230 GMT) in the Bolan Pass."

Baluchistan police chief Chaudhry Mohammed Yaqoob said the blast was apparently caused by a time bomb. "A man may have come on the bus and left it there and it exploded later," he said.

Sherpao said it was too early to say who was responsible. Baluchistan has been troubled by a growing insurgency by tribesmen seeking greater autonomy and more benefits from the province's natural gas resources, Pakistan's main source.

On Saturday militants fired more than 100 rockets into the town of Sui, killing two military guards and six civilians and damaging 16 houses, police said. Sui is near Pakistan's main gas field and about 720 km (450 miles) southwest of Islamabad.

The attack followed a similar rocket blitz on Friday and Saturday in the nearby town of Dera Bugti.

The area's senior government administrator, Abdul Samad Lasi, said militants also blew up a section of gas pipeline and a water pipeline in Dera Bugti overnight, while a landmine blast on Sunday morning killed a civilian on Sunday morning in nearby Kohlu district.

Speaking earlier, Sherpao said security forces were currently limiting their activity to defensive action but warned that "this strategy can be changed for the protection of gas installations and local population".

"Attacks on national installations cannot be tolerated," he said.

The latest violence came after President Pervez Musharraf demanded on Friday that Baluchistan's tribal leaders disband their "private militias".

The military launched a major crackdown on militants after a rocket attack on Dec. 14 during a visit by Musharraf to Kohlu. The crackdown coincided with the announcement of plans to privatise two gas distribution firms in Baluchistan.

Baluchistan nationalists say hundreds of people have been killed.

Analysts say this could be an exaggeration, but the independent Human Rights Commission of Pakistan has accused the government of "gross human rights violations" in Baluchistan.