A SEPTA transit police officer caught on a bystander's video throwing a man to the ground June 4 has been investigated and disciplined, but will remain on the force, SEPTA Transit Police Chief Thomas Nestel III said Friday.

Matthew Sinkiewicz, who Nestel said has been an officer with the department for about a year, can be seen in the minute-long clip ordering Anthony Barlow to sit down at SEPTA's Frankford Transportation Center. After Barlow verbally declines to sit several times, Sinkiewicz grabs him and forces him to the ground.

Nestel, who was alerted to the video via Twitter the same day, tweeted at the time that the incident would be investigated by Internal Affairs. He said Sinkiewicz was apprehending Barlow for obstructing walkways by dancing at the center, for which a citation was issued.

Although Nestel said department policy prevents him from disclosing how Sinkiewicz was disciplined, he said the officer did not appropriately respond to Barlow's "passive resistance." Sinkiewicz also violated the department's body camera policy by recording only his contact with Barlow and not Barlow's behavior prior to the incident, Nestel said.

"That's unacceptable to me," he said at a news conference. "It could have resulted in injury."

The department equipped its officers with body cameras in January following a pilot program in July 2014.

The body camera video, shown by Nestel at the news conference, shows Sinkiewicz handcuffing Barlow before ordering him to sit. The cellphone video begins with Sinkiewicz's telling the person recording to step back and that he was "going to get locked up."

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