TIME said it has expressed concern to the Secret Service following a violent confrontation between an agent and a photographer working for the publication at a Donald Trump rally.

The incident — which occurred as Black Lives Matter protesters were being escorted out of the event in Radrod, Virginia — was captured on video by bystanders.

Videos circulated on social media show the photographer, Christopher Morris, swearing at a Secret Service agent who apparently tried to prevent him from leaving the press pen.

A separate video shot from another angle shows the agent grab Morris’ throat with two hands, swing him around and violently slam the photographer to the ground.

A third video shows Morris on the ground kicking the agent away and, after getting up, accusing the agent of grabbing his neck as security swarms in. Morris then places his hands on the agent’s throat before he is pulled away by security and escorted out of the building.

“I just, I stepped 18 inches out of the pen then they grabbed me by the neck and started choking me and slammed me to the ground,” Morris told NBC News after he was released from a short detention by the Secret Service. “I never punched him, I never touched him.”

Morris said he placed his hands on the agent’s neck to demonstrate what had happened to him.

TIME said it has contacted the Secret Service to “express concerns about the level and nature of the agent’s response.”

“We are relieved that Chris is feeling OK, and we expect him to be back at work soon,” TIME said on its website.

The Secret Service has said its local field office was working with law enforcement to determine “the exact circumstances that led up to this incident,” and the Trump campaign directed inquiries to local law enforcement.

The campaign has been criticized for its strict rules regarding press at its events — including preventing their freedom of movement and ability to speak to attendees. Trump himself has been a vocal critic of the media and singled out specific journalists in his speeches at rallies.

Moore said he was “shaken” but physically OK, calling Monday’s incident “unfortunate and unexpected.”

“The rules at Trump events are significantly stricter than other campaigns and make it very difficult to work as a photographer,” he said in a statement via TIME. “I regret my role in the confrontation, but the agent’s response was disproportionate and unnecessarily violent. I hope this incident helps call attention to the challenges of press access.”

This story first appeared on NBCNews.com.