In retaliation for Pakistan''s aggressive air assault on the tribal region this week, the Taliban declared "open war" and bombed a minibus Tuesday carrying 18 Pakistani air-force personnel on a major road in Peshawar. Up to 14 people were killed.

The flurry of violence continued late Tuesday, as Pakistani military and intelligence officials said a missile strike on a suspected militant training camp near the Afghan border killed at least nine people. The officials said at least four missiles struck in the South Waziristan tribal region.

The site of the earlier airstrikes, Bajur, is a rebel sanctuary north of Peshawar along the rugged Afghan-Pakistan frontier where Taliban and al-Qaida forces are particularly strong. It is reckoned to be a possible hiding place for Osama bin Laden and his deputy, Ayman al-Zawahri.

It also abuts Kunar province in Afghanistan, where U.S. forces have suffered greater casualties in the past two months as they have confronted an increasingly tenacious Taliban insurgency.

Pakistani security officials said their recent airstrikes had broken the Taliban''s siege around Khar, the capital of Bajur, where emboldened rebels had been digging trenches in an apparent effort to encircle the town and overrun it. The offensive killed dozens and forced tens of thousands to flee to camps farther north.