The footage shows a white man in a cowboy hat walk down the row to the aisle where protesters are leaving and sucker-punch an African-American man, later identified as Rakeem Jones.
WRAL reports that the suspect, John McGraw, 78, was charged with assault and battery on Thursday.
Moments before the attack, the protester appeared to wave a middle finger at the crowd on his way out. Men in uniforms that read “Sheriff’s Office ” were leading the protesters away.
Jones accused Cumberland County officers of failing to protect him.
“The police jumped on me like I was the one swinging," he told The Washington Post.
“My eye still hurts. It’s just shocking."
An official from the Cumberland County Sheriff’s Office defended the deputies' actions at the rally on Wednesday.
"Our mission was to make sure all the 14,000 people stay safe, to separate protesters from supporters and to exit them as quickly as possible. What we did was to de-escalate the situation," Sgt. Sean Swain told The Huffington Post.
Swain also cautioned not to take a "10-second video out of context," referring to a moment where Jones is lying on the ground with deputies surrounding him, adding that "you don't know whether he fell or whether he was taken to the ground."
"When we look at all the video, we'll make final determination what took place," he said.
The sheriff's office has denied its officers detained the protester.
It's not the first time violence has broken out at a Trump event. The real estate mogul himself said last month he'd like to punch one of the protesters being led out of a rally in Las Vegas.
Author: Laura Barron-Lopez