British Royal Marine Commandos are joining other U.S.-led coalition forces in continuing offensive military operations in eastern Afghanistan against remaining Taliban militia and al-Qaida forces, a U.S. defense official says.

Members of the 41 Commando unit are participating in Operation Mountain Lion, an ongoing U.S. operation in eastern Afghanistan, Air Force Brigadier General John Rosa said April 16 at a Pentagon briefing. The unit specializes in high mountain and extreme cold weather warfare.

Pentagon officials said the aim of the current operation is to find the enemy fighters, destroy those that are there and deny them control of the area and an opportunity to reorganize their forces. Operation Mountain Lion is the first major initiative since Operation Anaconda, a 12-day running battle which ended last month in the eastern Shah-i-Kot Mountains, Rosa said.

"This mission, involving British forces, that began yesterday [April 15], exemplifies the diversity and versatility that coalition participants provide in the execution of operations in Afghanistan and worldwide in the Operation Enduring Freedom," Rosa said.

Rosa would not provide details about the Marine Commandos' area of operations, but said the 1,700-member force will be integrated into current operations and lend their special expertise to the problem. He did say that the operations are being conducted in Paktia province, which is in eastern Afghanistan adjacent to the Pakistan border.

In addition, Rosa said U.S. forces have been working closely with Pakistani special forces and conventional forces to seal the border in the contested region, but U.S. forces have not chased the al-Qaida and Taliban forces across the border.