Updated

Efforts to train thousands of federal agents to protect commercial flights during heightened terror alerts were quietly abandoned more than a year ago because Congress objected to the cost, government investigators said Tuesday.

The Government Accountability Office, an investigative arm of Congress, reported that the federal air marshal service suspended its efforts to develop such a "surge capacity" by training customs and immigration agents to protect passenger airliners.

The Homeland Security Department "indicated that it would continue to support the surge effort but had not determined whether and when it would resume cross-training to resume this initiative," the report said.

The plan was first disclosed in September 2003 by Tom Ridge, then Homeland Security secretary.

Ridge announced that the air marshals would be combined with immigration and customs agents in the same agency so agents in both could be cross-trained and used for aviation security. The move would allow more than 5,000 armed federal law enforcement agents to be deployed on commercial aircraft, he said.

"This realignment offers a sweeping gain of additional armed law enforcement officials who will be able to provide a 'surge capacity' during increased threat periods or in the event of a terrorist attack," Ridge said at the time.

By October 2004, Homeland Security had cross-trained some immigration and customs agents, but stopped because of congressional concerns that it was "an ineffective use of resources," the report said.

The number of immigration and customs agents who were trained wasn't disclosed for security reasons. The assistant secretary for the agency, though, testified in March that 800 agents would be trained by October, the report said. Some of those agents were assigned to augment air marshals on flights during heightened threat alerts.

The air marshals moved back to the Transportation Security Administration in October.

The air marshal program was nearly nonexistent at the time of the Sept. 11 attacks. Only 32 agents were employed then, but the number increased into the thousands after the hijackings. The exact number is classified.