A United passenger is banned from future flights after witnesses say he punched a crew member and tried to jump out of the plane

• A United Airlines flyer reportedly became violent after he was told to leave someone else's seat.
• He then opened the emergency exit and attempted to jump from the plane, a witness told ABC 7.

A passenger has been banned from traveling with United Airlines after witnesses said he punched a crew member and tried to jump out of the plane during boarding. A United spokesperson confirmed the incident to Insider.

"This customer's behavior was unacceptable," a representative told Insider in a statement. "He has been banned from future United flights and we are working with local law enforcement in their investigation."

The incident happened around midnight on May 1, according to the local news outlet ABC 7. The United Flight was preparing to take off from San Francisco International Airport on its way to Houston when Naya Jimenez, a passenger on the flight, told the outlet that she asked the man and his wife to move from her assigned seat.

Things escalated, Jimenez said, after an employee stepped in.

"They had to bring in a gate attendant to try to talk to both of them," Jimenez told the outlet. "Then, he began slurring his speech a little bit, like, 'Sir, why are you smiling at me?' That's the first thing he said."

Video of the incident shows the man repeatedly swinging at the employee and other passengers as people attempted to restrain him. Then, Jimenez said, the man ran towards the emergency exit.

"After he paused for a minute, he ran toward where the pilot was, where the emergency exit doors are, and attempted to open it," Jimenez told the ABC affiliate. The passenger, she added, "successfully opened the emergency exit and was about to jump down."

"The flight attendants just kicked in, and everybody pulled him back to safety," she continued.

"On Sunday night, our team at San Francisco International Airport immediately contacted law enforcement officials after a customer became disruptive during boarding," a United Airlines representative told ABC 7 in a statement. "We're grateful to our team in San Francisco for their professionalism in this situation and for looking out for the safety of our customers and their fellow United employees."

In a statement to Insider, a United representative said that the San Francisco team had contacted law enforcement after the altercation, though it wasn't immediately clear whether the passenger had been arrested. United is working with local law enforcement in an investigation, the spokesperson told Insider.

It's the most recent example of a passenger being removed for unruly behavior. In late April, the reality TV star Savannah Chrisley said she was "thrown off" a Southwest flight after refusing to check her bag.

That same week, a United flight had to turn around three hours after it took off when a man reportedly sat in a crew seat and got "in a shouting match" with a flight attendant.