A wild fight at a Pennsylvania carnival has sparked a police investigation after an officer was seen on cellphone video appearing to put a teenage girl in a chokehold while a second policeman slams another girl to the ground.

The incident happened Saturday night at the annual St. Francis Spring Carnival in Norristown when police were called to break up a massive brawl involving around 50 teenagers, according to NBC Philadelphia.

In footage of the melee, an officer is seen on the ground with his arm tightly around a teenage girl's neck as she appears to cry. Several teenagers are surrounding the officer.

When one girl from the crowd takes a step toward the officer, he swings at her. She responds by punching the officer several times in the head. A second officer comes to the first officer's aid and slams the girl to the ground.

A police spokesperson declined to name the officers involved and said in a statement Monday that the department was investigating the matter. The policemen involved remain on duty, the spokesperson said.

"We’ve received several videos and social media posts regarding how the officers conducted themselves. A full and thorough investigation is being conducted. We are committed to uncovering all of the relevant facts and will proceed transparently and impartially," the statement read.

The girl placed in the headlock told NBC Philadelphia that she repeatedly told the officer choking her that she couldn't breathe, but he would not let go.

A video captured an offficer using a chokehold on a teenage girl while breaking up a melee at a carnival in Norristown, Pennsylvania. Marcus Melle / via NBC Philadelphia

"It was pressing on my neck. ... It was terrible," the 14-year-old said, telling the outlet that police mistakenly thought she had been involved in the earlier fight.

She also said her cousin was the girl who was slammed to the ground. NBC Philadelphia reports that the cousin was arrested and remains in custody.

Police Chief Mark Talbot Sr. addressed residents' concerns during an open forum Sunday.

"This is not a racist police department," he said. "This wasn't an act of terror by the police. These officers were overcoming a significant amount of resistance."