On July 21 at 8:17 p.m., four male juveniles met in the 100 block of South Old Glebe Road for a prearranged sale, Arlington police said.
The three suspects assaulted the victim and stole his backpack, which contained a laptop, police said.
A lookout was broadcast and responding officers located one of the suspects, who was carrying stolen property, and attempted to stop him. He was taken into custody following a foot chase. Petitions are pending.
The victim was taken to a local hospital for treatment of injuries described as non-life-threatening.