Police are appealing for witnesses after a 15-year-old boy was assaulted near Waveney Community Centre at Glendun Park in the town.
The teen was assaulted by three males - all in their late teens and wearing tracksuits - at around 4.30pm on July 14.
The teen suffered injuries and had personal possessions taken from him.
The attackers made off in the direction of Doury Road.
Anyone with information is asked to contact police in Ballymena on 101.