WATCH | Police officer 'punches' woman in beach arrest viral video

Police have opened an investigation after a video emerged showing what appears to be an officer punching a woman in the head during an arrest in New Jersey over the weekend.

The video, which surfaced on Saturday, shows officers wrestling Emily Weinman to the ground at Wildwood beach. One officer can be seen punching her in the head before placing her in a headlock and pinning her to the ground.

Weinman, who is wearing a swimsuit and pair of shorts, can be seen kicking an officer when he tries to hold her down. 

She can be heard shouting: “You’re not allowed to hit me like that… I didn’t do anything wrong”.

In the background, eyewitnesses can be heard urging the twenty-year-old to stop resisting the officers.

The Wildwood Police Department has launched an internal investigation, while the officers involved have been put on administrative duty. 

Weinman was charged with two counts of aggravated assault on a police officer, aggravated assault by spitting bodily fluids at/on a police officer, disorderly conduct, resisting arrest, obstruction and minor in possession of alcohol.

Alexis Hewitt, who captured the incident on video, told ABC News she was with friends when she was startled awake by the commotion.

"When she fell that's basically when it caught my eye because everyone was yelling and I woke up, and I got my camera out right when she went down," Hewitt said.