From ABC:

Federal air marshals subdued a man who authorities say attempted to “light his shoes on fire” on a United flight from Washington Reagan to Denver Wednesday night, federal law enforcement officials told ABC News.

Authorities say an explosive team is on the way to the airport, and that while the presence of explosives has not yet been confirmed, they believe it was an attempted “shoe bomb.”

The suspect was identified by authorities as a diplomat in the Qatar embassy in Washington, Mohammed al Modadi. The FBI said the man had full diplomat immunity as the 3rd secretary and vice-consul.

Authorities said two jet fighters were scrambled from Buckley Air Force Base to accompany United flight 663, a Boeing 757, as it flew the final 40 miles to Denver where it landed safely.

Authorities said the man, identified as from Qatar, was restrained by the air marshals who were on the flight.

Coming up tomorrow – nonstop interviews with Dick Cheney.

UPDATE (10:40):

Per Pete Williams on MSNBC there is no shoe bomb. Apparently the suspect spent an extra long time in the bathroom. When he finally came out an air marshal said he smelled smoke and asked the suspect what he was doing. The suspect responded “trying to light my shoes on fire”. They now believe he was smoking a cigarette in the bathroom.