WATCH: Cop knocks down and handcuffs 9-year-old black kid for leaning against a car

Washington D.C. police say they are investigating an incident in which an officer chased down a 9-year-old black boy and handcuffed him while he cried, reports FOX 5.

Onlookers recorded the incident and posted it to social media.

Now, his mother is demanding answers.

FOX 5 asked the police department chief about their policy regarding handcuffing kids.

“It just depends on whether the officer feels that there is a threat or what situation led up to. We have juveniles that are involved in all sorts of different activities within the city. Certainly, we will get to the bottom of this,” MPD Patrol Chief Lamar Greene told FOX 5.

Mayor Muriel Bowser also seemed reluctant to criticize the police department.

"Every case is different," said Bowser. "I would also suggest you not promote pictures of juveniles in this situation."

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