A Qatari diplomat has been detained on board a US passenger jet on suspicion of attempting to set off a bomb.

Passengers and crew on the United Airlines flight from Washington to Denver overpowered the diplomat because they thought he was trying to set fire to his shoes. An investigation proved he had no explosives in his possession. US media report that the diplomat had probably been smoking a cigarette in a plane toilet and was trying to put it out with his shoe when he was discovered.

The suspect reportedly made a joke about it and said he wanted to set his shoe on fire. The authorities raised the alarm and F-16 jet fighters were scrambled to escort the passenger jet to Denver airport. The diplomat, who has been living in the United States for years, is still in custody.