Unruly Passenger Dancing and Singing 'Really Loudly' Causes Delta Flight to Divert

A male passenger forced an Atlanta-bound Delta plane to divert to Tulsa, Oklahoma (TUL), after he became unruly mid-flight.

Delta Flight 1156 was headed from Portland (PDX) to Atlanta (ATL) on Wednesday when the man became aggressive toward a flight attendant while the plane was mid-air. The man was so unruly that federal air marshals on board had to intervene and subdue him.

Witnesses say the man was singing and dancing while the flight was boarding at PDX, and he began to do so again in-flight before lashing out at the aircraft cabin crew. “All in all, it was a crazy flight,” passenger Lisa Zimmerman told ABC News.

According to Zimmerman, the man “started singing really loudly” during the flight. When a flight attendant tapped him in an effort to tell him to stop, Zimmerman said the man "flipped." "He threw off his headphones and said, ‘Touch me again and you’ll regret it,’” she said.

After that, the federal air marshals intervened and “successfully de-escalated and the controlled the situation,” US Attorney R. Trent Shores told ABC.

Delta told TPG the 737-900 aircraft landed "without incident" in Tulsa, and the passenger was met by law enforcement after deplaning. "Delta apologizes to our customers delayed by this diversion," an airline spokesperson said in a statement.

There were 172 customers, 6 working crew on board.

The FBI is investigating the incident. It's a federal crime punishable by a fine and/or prison time to interfere with the duties of a flight attendant by assault or intimidation.

*This post has been updated with Delta's statement to TPG.