PHILADELPHIA (CBS) -- Philadelphia police say the East Detective Division is working to identify a number of teenagers seen assaulting and robbing a person. The video is difficult to watch. At a minimum, police say this is a robbery.

The attackers taped their crime.

The location of the hold-up and beatdown is unclear.

The video surfaced on social media earlier this week.

Police say they have not yet heard from the victim.

They're encouraging him to contact them.

If you know the people in the video, call the Philadelphia police.