PHILADELPHIA (CBS) — The Philadelphia Police Department is conducting an internal affairs investigation after a video went viral on social media allegedly showing a white police officer temporarily detaining a black teenager who was waiting at a North Philadelphia bus stop. In the video, the officer can be heard telling the teen, “Remember, you were shaking in the police car.”

Police say the incident took place last Thursday around 3:25 p.m. at 23rd Street and Cecil B. Moore Avenue.

Cops reportedly harassed a group of kids for waiting at a bus stop and even ordered one Black teen into their car with no explanation pic.twitter.com/ZRnhLQ7CAj — NowThis (@nowthisnews) September 17, 2019

The Daily Dot reports 16-year-old Asia Wilkerson posted the video of the incident. According to Asia’s Twitter account, she and a group of students were waiting at a bus stop when the officer slowed down, stared at them, left and returned with backup.

Asia tweeted that the officer grabbed the teen “aggressively” and placed him in the back of the police vehicle. She said they refused to get on the bus until the teen was let out of the vehicle.

The officer then let the teen out, and said to him, “Remember, you were shaking in the car.”

Police say they are aware of the incident.

Philadelphia Police Department statement regarding the detainment of a citizen, which occurred 9/12/19 in the area of 23rd Street and C.B. Moore Ave: pic.twitter.com/IyKcv4pt1v — Philadelphia Police (@PhillyPolice) September 18, 2019

“We take all matters involving the stopping, detainment, and investigation of citizens very seriously. Accordingly, we immediately initiated an internal affairs investigation,” police say.

Mayor Jim Kenney says he’s “concerned” with what happened on the video.

“I’m concerned by what I saw on the video and know that incidents like this can cause distrust among residents and our officers,” Kenney tweeted.

I’m concerned by what I saw on the video and know that incidents like this can cause distrust among residents and our officers. We are investigating, and we remain committed to building stronger relationships between police and the communities they serve. https://t.co/cyhkciB0C5 — Jim Kenney (@PhillyMayor) September 18, 2019

Police are asking anyone with information about this incident to contact police at 215-685-5056.

The officer’s name has not been released.