A Massachusetts Bay Transportation Authority Police officer is under investigation after a video surfaced on Friday showing him hitting an unarmed black woman with a baton and pointing his gun at witnesses. The officer, whose name has not been released, is black. He has been placed on administrative leave.

The incident happened aboard Bus #15 in Boston. The video, which was posted to Facebook by activist group Mass Action Against Police Brutality, begins with the officer hitting the woman with his baton. She grabs it to stop the beating, amid cries from witnesses for the officer to stop. When three women approach to ask the officer to leave the woman alone, he points his gun at them and the passengers flee to the other end of the bus. The young woman attempts to get away from the officer, who repeatedly yells “back up” and “shut the fuck up.” The crowd in turn yells, “Drop the gun” and tells the woman to calm down. When backup arrives, another officer points his gun at the passengers and tells them to get off the bus. After the woman is cuffed, the witnesses yell that one of the officers is pulling her hair. The action is not visible on the video, which by then was being shot through the bus window.

According to audio of a statement from MBTA Lieutenant Richard Sullivan that plays in the second half of the video, the woman had been identified as someone involved in a theft and she did not comply when the officer told her to get off the bus. “If you saw the video in the beginning, the officer asks that woman to step off the bus so he can conduct an investigation. She refused to do so, and became actively non-compliant and assaultive,” he said. That conversation does not appear on the video.

Sullivan goes on to say that the unidentified transit cop is a well-respected veteran officer. He declined to comment on the officer’s use of force or his decision to draw his gun on the passengers. “It wouldn’t be fair or appropriate for me to comment on the actions that took place within the bus because, like I said, it’s going to be investigated,” he said.

The video is below.

(H/t ThinkProgess)