Afghan officials say scores of Taleban insurgents have captured at least one district in southern Afghanistan after a 16-day standoff with local security forces. The official statement followed an earlier announcement by U.S. military officials that a massive counter-insurgency operation in the same region seriously disrupted Taleban forces.

Afghan presidential spokesman Karim Rahimi confirms that Taleban insurgents seized two towns in southern Helmand province two days ago. Rahimi says local police held the area for 16 days before the Taleban forces overran one village near the border with Pakistan.

As soon as the police pulled out, he says, truckloads of Taleban militants drove in from across the border and took over the entire area.

U.S. officials said late Tuesday coalition forces already have the area under observation and will soon take what they called "decisive action" to re-establish government control.

Hours earlier, U.S. officials said a much broader U.S.-led counter-insurgency operation seriously weakened Taleban forces in much of southern Afghanistan.

Operation Mountain Thrust was launched last month and involves more than 10,000 U.S., Afghan, and other coalition forces targeting Taleban militants in four southern provinces.

U.S. military spokesman Colonel Tom Collins says the operation has killed numerous low and mid-level Taleban commanders. He says the push has disrupted the Taleban's operational capacity, particularly in the provinces' northern districts.

"The enemy is under intense pressure in those areas," said Collins. "We know the enemy is now moving into deeper southern parts of the southern provinces in an effort to escape the coalition, and more importantly, to pick targets that are lightly defended because of a lack of government presence."

U.S. and Afghan officials say the operations will continue until the insurgency has been defeated.

Taleban militants began a major offensive several months ago. Afghanistan is enduring its bloodiest year since the hard-line Islamist group was forced out of power in 2001.

More than 700 people, mostly militants, have been killed since May.

The hardest hit areas were in southern and eastern Afghanistan, the Taleban's traditional strongholds.