According to American Airlines, Flight 976 from JFK International Airport to John Wayne Airport in southern California was diverted to Denver after the assault.
A photo tweeted by a passenger shows the man who was arrested sitting inside the terminal at the airport in Denver. He is seen handcuffed and wearing a mask.
The airline initially said he punched a female flight attendant over his refusal to put a mask on in the first place.
However, ABC News has confirmed that the assault on the attendant was not related to a mask violation. A source familiar with the investigation said it was an unprovoked attack.
While in the aisle, the flight attendant accidently bumped the first class passenger earlier in the flight and quickly apologized. Later on, the passenger walked to the galley area, punched the flight attendant twice and then returned to his seat as if nothing happened.
Passengers say the man had to be duct taped to his seat, and they say alcohol was involved before things turned violent.
"I understand that they actually punched her twice," said one passenger. "I did see her walk back down the aisle afterwards. She had blood splattered on the outside of her mask."
"Yeah there was a doctor on the flight luckily, so I don't know," said another. "He said (her nose) wasn't broken but she was bleeding so they took her to the hospital."
The plane landed safely and taxied to the gate, where law enforcement removed the passenger and took him into custody. It eventually continued on to California, where it landed safely at John Wayne Airport in Santa Ana.
"We are outraged by the reports of what took place on board. Acts of violence against our team members are not tolerated by American Airlines. We are working with law enforcement to support our team member and pursue prosecution, and the individual involved in this incident will not be allowed to travel with us in the future," American Airlines said in a statement.
"In terms of men hitting women, it's absolutely absurd and ridiculous. Violence is never the way," said Mackenzie Rose, the passenger who tweeted the photo
Reports of unruly passengers are way up during the pandemic.
The FAA reports close to 5,000 incidents, 72% involving face masks, resulting in 216 enforcement cases - and more than $1 million in fines.
Assaulting a flight attendant is also a felony, with offenders facing potential prison time of up to 20 years.
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