American forces worked with Philippine soldiers on Basilan as part of a six-month counterterrorism exercise that ends Wednesday. A year ago, Philippine officials estimated Abu Sayyaf had about 1,200 followers on the island and 140 more scattered on other islands.

"I think that if they go back to Basilan, they are going back to a different place," Brig. Gen. Donald Wurster said in an exclusive interview Tuesday with Associated Press Television News.

Wurster said the Philippine military has been bolstered by the six-month training exercise.

Of Abu Sayyaf, he said: "With what is in the future for them, I think they ought to take up another line of work because they are going to have an unlucky day and it's going to be the end of them and the world will be better for it."

The extremist group "has not begun to feel the potential that the AFP (Armed Forces of the Philippines) is growing into," said the commander of more than 1,000 U.S. troops in the southern Philippines.

Abu Sayyaf is believed to have seized 102 hostages, including three Americans, in a yearlong kidnapping spree that ended last month. That's when U.S.-trained soldiers, helped by U.S. surveillance and communications, tracked down Abu Sayyaf fighters holding the last three hostages: American missionaries Gracia and Martin Burnham and Filipino nurse Ediborah Yap.

On June 7, soldiers rescued Mrs. Burnham, but her husband and Yap were killed. The Abu Sayyaf leader who led the kidnappings was believed killed with two of his men in a clash at sea two weeks later.

The mission in the Philippines was the first expansion of the U.S. war on terrorism outside Afghanistan. It involved American soldiers training Filipino troops in marksmanship, leadership, special operations, intelligence, communications and survival techniques.

The operation involved deployment of U.S. troops in a combat zone and lasted much longer than normal joint maneuvers. Limited to shooting in self-defense, the Americans' sole clash came when a Marine security detail came under fire from suspected guerrillas last month. There were no U.S. casualties, although 10 Americans were killed in a helicopter crash early in the exercise.

Philippine Brig. Gen. Emmanuel Teodosio, co-director of the exercise, said the Filipino soldiers emerged as "a better fighting force."

"More than the technical expertise that we have gained ... is the renewed resolve and fighting commitment of our men because of the improvement in their confidence as provided by the training," he said.