Fairfax County police have opened an internal investigation after a reporter from a liberal media outlet was taken to the ground and arrested Saturday following an argument with police officers as he was attempting to cover Virginia Republican gubernatorial candidate Ed Gillespie.

During the incident, part of which was captured on video, Fairfax County police officers could be seen arguing with Shareblue Media’s Mike Stark before the confrontation grew physical and he was arrested at a parade in Annandale, Va.

Stark said Tuesday that police improperly handled the situation, but Fairfax County police chief Edwin C. Roessler Jr. defended the officers involved, saying Stark was being disruptive and using foul language at a family-oriented event.

The incident began when a police officer asked him to stay away from a van carrying Gillespie as the parade was about to begin, Stark wrote in an email to The Washington Post.

Stark said he told the officer that he was a reporter and that he would be covering Gillespie, who is squaring off against Democratic nominee Ralph Northam in a race that has gained national attention.

Roessler said Stark was in a roadway that was on the parade’s route and was asked to move.

In a portion captured on video that was filmed by someone other than Stark, an officer can be heard asking Stark to step back from a roadway. The pair argue as Stark backs up onto a sidewalk.

“I’m just a reporter doing my job,” Stark is heard saying at one point.

“If you curse again, you will go to jail,” a second officer later tells Stark.

Stark then yells loudly: “F--- this!”

The first officer then turns Stark around in an apparent effort to handcuff him and pushes him up against a fence. The two officers then struggle with Stark, before one pulls out Stark’s leg and pushes him facedown onto the sidewalk.

The two officers pile on Stark, who can be heard saying “Stop, I will give you my arm.” Stark is then swarmed by three other officers who help pin him down and attempt to handcuff him. Stark can be heard screaming, before he is eventually handcuffed.

One of the officers claims in the video that Stark is being arrested for public swearing, but court records show Stark was taken into custody for disorderly conduct and avoiding arrest. Shareblue said he was released on a $3,000 bond.

“I think they were letting me know who was boss,” Stark wrote in an email to The Post. “It was unnecessary, unlawful and violent, but not brutal.”

Stark said he suffered superficial wounds in the incident and refused medical treatment.

Roessler held a Tuesday evening press conference to defend the officers’ actions, saying at one point an officer even tried to de-escalate the situation by walking away from Stark before the altercation.

“I’m standing before you to defend the lawful actions of my police officers enforcing the law and protecting the community at a parade,” Roessler said. He later added the officers will remain on active duty during the internal probe.

Reporters have seen Stark shouting confrontational questions to Gillespie at the candidate’s events. He has also told reporters he shares videos with American Bridge, a Democratic political action committee.

Shareblue, Stark’s media outlet, is owned by David Brock, the founder of Media Matters for America.