Authorities: Alleged shoe bomber did not act alone

WASHINGTON (CNN) -- Authorities said Friday they have forensic evidence that proves alleged would-be airplane shoe bomber Richard Reid did not act alone in making the bombs found in his sneakers.

U.S. government sources and intelligence sources overseas told CNN's Susan Candiotti that palm prints and hair samples not belonging to Reid were discovered in the bombs hidden in his shoes.

Extensive lab analysis by the FBI led to the conclusion, the sources said.

Reid has said he had no help building the bombs, but investigators -- citing the bombs' sophistication -- have never been convinced.

Sources say Reid, a 28-year-old British citizen and convert to Islam, has told authorities he paid $1,500 in Amsterdam to a man from the Czech Republic for the bomb-making materials.

Those materials included PETN and TATP, both easily obtained but highly volatile. TATP has been used by Hamas bombers in attacks in the Mideast.

Reid is charged with attempting to blow up American Airlines Flight 63 as it flew from Paris to Miami last month.

A flight attendant caught him trying to ignite one of the bombs with a match, and tried to stop him, authorities say. Other passengers joined in and subdued him. The flight was diverted to Boston's Logan International Airport.

Reid, who is under a suicide watch at a Massachusetts detention center, has pleaded not guilty.