BROOKLYN, N.Y. - Police are investigating the violent robbery of a 19-year-old man in Brooklyn earlier this month.

Surveillance video from October 8 shows three people chasing down the victim and pushing him to the ground in front of 619 56 Street in Sunset Park where he was punched and kicked.

Police say the attackers cut the straps of the victim's backpack with a knife and ran off with the bag.

The victim was treated at the hospital for a cut to his head.

Anyone with information on the case should contact the Crime Stoppers hotline at 1-800-577-8477, or text CRIMES and then enter TIP577, or visit