A U.S. military source said Thursday the three-member crew of a U.S. helicopter was shot to death by rebels after safely landing their helicopter, which had been hit by rebel fire.

The Pentagon said the UH-1H Huey transport helicopter was shot down by small arms fire about five miles north of Lolotique, in eastern El Salvador.Wednesday's attack came five days after the rebels announced an end to their offensive.

"They managed to get the aircraft down all right," said the source, who spoke on condition he not be identified. He said the crew was shot to death after safely landing the chopper, which was damaged by small-arms fire.

The Pentagon confirmed that the three U.S. Army crew members were killed.

Washington has been considering sending more than $40 million to the right-wing government of President Alfredo Cristiani as a result of the six-week rebel offensive, in which more than 600 people died.