Fierce fighting continues in eastern Afghanistan between American-led forces and remnants of the Taleban and the al-Qaeda network. The fighting now appears to be some of the heaviest of the anti-terrorist campaign in that country. The operation is shaping up to be a prolonged one.

U.S. forces continued their assault, Monday, in the Shah-e-Kot Mountains in Paktia Province.

For the fourth straight day, American warplanes dropped thousands of pounds of explosives on al-Qaeda and Taleban positions. Afghan forces - accompanied by U.S. soldiers - engaged in heavy firefights with al-Qaeda fighters.

The progress of the fighting cannot be independently confirmed, because of U.S. military secrecy and the remote location of the battle front. However, wounded Afghan fighters have said the ground assault - which began early Saturday - stalled when it ran into unexpectedly heavy resistance.

Estimates of the force arrayed against the American assault range from several hundred to several thousand al-Qaeda and Taleban fighters. Analysts believe the rough terrain and the fanatical determination of the opposition will likely make the task of the U.S. effort long and difficult.