WATCH: Unruly Trump Fan Delays Shanghai Flight to US

By Bridget O'Donnell

A United Airlines flight from Shanghai to Newark, New Jersey was delayed for five hours and eventually rerouted to San Francisco International Airport over the weekend after an unruly, Trump-supporting passenger caused a commotion during take-off.

The unidentified passenger was spotted wearing a red "Make America Great Again" hat, which was made famous by Donald Trump's 2016 campaign.

United says the Trump fan tried to grab another passenger's seat while boarding flight UA87 at Shanghai Pudong International Airport on Sunday, refusing to move and causing a ruckus.

As the man became increasingly disruptive, passengers were forced to de-plane while law enforcement sorted things out. The man was eventually kicked off before the flight departed. Fellow passengers, in a mocking nod to the embattled US President, shouted "Lock him up!" as he was escorted back to the boarding gate.

The flight, which is normally over 14 hours long, was scheduled for a 3.45pm takeoff but actually departed at 8.44pm. Following the five hour delay, it was later forced to make an unscheduled stopover in San Francisco to bring a new crew on board. Passengers remained on the plane for less than an hour while the switch happened.

That's has received video from one passenger on the flight, who captured the commotion before and after the Trump supporter was taken off the plane. A fellow passenger can be heard telling the man: "You don't have manners! You are rude!"

https://v.qq.com/txp/iframe/player.html?vid=r0505ju8ory&width=500&height=375&auto=0

More footage obtained by NBC shows fellow passengers jeering him on at the gate after he was booted from the flight.

American citizen Jonathan Serbent, another passenger onboard the flight, described the incident to That's:

"I didn't hear everything that happened since I was trying to ignore it, but he was across the plane, about two rows ahead. From what I heard them saying to him and from people later on it sounded like he wanted the seats next to him to be empty, even though he didn't purchase those seats. 

"He was being very rude about it and causing a big scene. He was asking that he get all sorts of benefits like access to the United Club lounge. It got to the point where I think because of all the commotion he was causing, he had to be removed from the plane. But, he was being stubborn and wouldn't move, so eventually United had to just clear the plane. 

"Everyone got off but him, and then about twenty minutes later he walked out with people escorting him. There was no violence whatsoever and United handled the situation very well. The worrying part was when passengers got annoyed and started yelling. But all in all the situation was handled really well, no one was hurt, and we made it to our destination."

Additional reporting by Emersyn Lyon

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