Philadelphia International Airport spokeswoman Victoria Lupica says the US Airways Flight 742 took off for Barcelona at about 7:50 p.m. Wednesday but returned at about 9:45 p.m. Police say the unidentified man was restrained by fellow passengers. No one was injured.
The plane was cleared to resume its trip.
Earlier Wednesday, officials said an investigation into a bomb threat made in connection with a different trans-Atlantic flight that landed in Philadelphia turned up nothing suspicious. US Airways Flight 777 from Shannon, Ireland, landed in an isolated part of Philadelphia International Airport, where its passengers were questioned, but nothing was found.