The Boston Police Department is investigating a video showing an off-duty police officer forcing a man to the ground.Watch the reportThe two men were involved in a confrontation just before Stephen Harlowe started recording. Watch the video here"The guy in the Red Sox jersey tackled him," Harlowe said. "Then took his head and slammed it on the sidewalk. And then he grabbed a handful of his hair and slammed it again."The officer then walked the man, who isn't being identified, because he hasn't been charged, back to the intersection of Boylston and Arlinbgton streets where the confrontation began.The video didn't show what led up to the chase."The victim was crossing in the crosswalk, and the officer turned the corner and cut him off," Harlowe said. "And he said, 'When he cut me off, I was scared, and I tapped his window with my umbrella.'"But investigators said the man admitted to jaywalking and crossing the intersection against the light.Police said he then struck the officer's car with the umbrella and ran off when the officer tried to speak with him.People who saw the chase said they feel the reaction was excessive, and police are interviewing witnesses as they review the officer's actions.

The Boston Police Department is investigating a video showing an off-duty police officer forcing a man to the ground.

Watch the report

The two men were involved in a confrontation just before Stephen Harlowe started recording.

Watch the video here

"The guy in the Red Sox jersey tackled him," Harlowe said. "Then took his head and slammed it on the sidewalk. And then he grabbed a handful of his hair and slammed it again."

The officer then walked the man, who isn't being identified, because he hasn't been charged, back to the intersection of Boylston and Arlinbgton streets where the confrontation began.

The video didn't show what led up to the chase.

"The victim was crossing in the crosswalk, and the officer turned the corner and cut him off," Harlowe said. "And he said, 'When he cut me off, I was scared, and I tapped his window with my umbrella.'"

But investigators said the man admitted to jaywalking and crossing the intersection against the light.

Police said he then struck the officer's car with the umbrella and ran off when the officer tried to speak with him.

People who saw the chase said they feel the reaction was excessive, and police are interviewing witnesses as they review the officer's actions.