Metro Police is investigating a use-of-force incident that occured at the U Street Metro station on Sunday.

The Metro Transit Police Department has opened an internal investigation in response to a video posted to Twitter on Sunday that showed a Metro officer using a taser on an unarmed man at the U Street/Cardozo station.

“Based on concerns raised on social media regarding the officer’s handling of the interaction, as well as the appropriateness of the use of force, the Metro Transit Police Department has initiated an investigation into the matter,” MTPD said in a statement released on Sunday night.

The video appears to show two men talking to Metro officers who are detaining a young man. Their exchange is cut short when a third officer approaches one of the men and shoves him. The officer then pulls out his taser and fires it at least twice as he and another officer force the man to the ground and place him in handcuffs.

The officer reported that he used his taser because the man was “interfering” with an ongoing investigation and “exhibit[ing] behavior consistent with preparing to fight,” according to MTPD’s statement. The incident started when the department received calls about “disorderly juveniles threatening Metro patrons on the platform with sticks,” the statement said.

As of Monday morning, no officers had been placed on leave while Metro conducts its investigation, an MTPD spokesperson told DCist. But the department declined to provide any further details, referring back to the statement released on Sunday.

Ward 1 Councilmember Brianne Nadeau said on Monday that she has been in touch with Metro Police Chief Ron Pavlik about the incident.

“The video leaves little doubt in my mind that what happened was unacceptable,” Nadeau told DCist in a statement. “Although this happened in Ward 1, it could have happened anywhere in the Metro system and that’s something all of our leaders across the region should be concerned about.”

She called for the officer to be “removed from contact with the public” until the investigation concludes.

Black Lives Matter DC quickly responded to the incident on social media, calling for the officer to be removed from Metro’s police force.

At-large Councilmember Robert White called the incident “terrifying” on Twitter and expressed concern that it would further undermine public trust in Metro’s police force.

This isn’t the first time that MTPD has come under fire for alleged excessive use of force.

Last year, Metro police injured a woman who tried to ride the bus without paying a fare, chipping her teeth and splitting her lip. In another fare evasion-related arrest months later, MTPD officers pinned a woman down at the Fort Totten station and threatened her with a taser.