U.S. hospitals are increasingly shutting down their burn centers in a trend experts say could leave the nation unable to handle widespread burn casualties from a fiery terrorist attack or other major disaster.

Associated Press interviews and an examination of official figures found that the shrinking number of beds is a growing cause for concern in this post-Sept. 11 world.

Experts say burn centers are expensive to maintain and often lose money because they are staffed with highly specialized surgeons and nurses and stocked with sophisticated equipment designed to ease patients' excruciating pain, fend off deadly complications and promote healing.

The number of burn centers in the U.S. has dropped from 132 in 2004 to 127, and burn beds have fallen from 1,897 to 1,820, according to American Burn Association records compiled from voluntary reporting by hospitals.

The U.S. Department of Health and Human Services puts the number of burn beds even lower, at just 1,500. And most of those are already filled, with the number available on any given day variously estimated at just 300 to 500.

"If something happens and we need the beds for burn patients, it is going to be a real catastrophe," said Dr. Alan R. Dimick, past president of the American Burn Association and founder of the burn center at the University of Alabama at Birmingham.