Police now say two suspects have been arrested and investigators are looking for a third. They also say this definitely appears to be a part of the so-called knockout game.
"It's a little disturbing to see kids engaging in this activity they thinks it's funny," Philadelphia Police Lt. John Stanford said.
After randomly punching the juvenile victim, two of the suspects proceed to further pummel him while a friend films and laughs.
Police say the attack happened Tuesday near Large Street and Cottman Avenue.
Initially there was no report of the incident, since the victim did not notify police after the attack. However, after the video was posted to Facebook, word of the incident spread, prompting calls to authorities.
"They sent the information to our social media manager via Facebook, as you know we are on Facebook, we are on Twitter, we are on YouTube, they sent the information over telling us to take a look at this," Stanford said.
Police say they quickly identified the suspects through social media and help from the school district.
One of the suspects was picked up Wednesday at Northeast High School. Another, who is in custody, goes to Woodrow Wilson Middle School - as does the victim.
The victim was brought into Northeast Detectives Wednesday with his father. He wasn't seriously injured and never filed a police report.
Police say other videos posted to Facebook indicate the attackers may have done this before.
"For someone to walk down the street and do this is not something new. You can see their demeanor and their actions, this just about something you can bet they've done before," Stanford said.
Police are continuing to search for the third suspect, but say they know who he is.
All three suspects face Simple Assault charges.