Police are appealing for information following reports of a fight in Crawley on 19 September at around 7.30pm.
The fight, which was reported to have been between two teenage boys, happened in Broadway.
Officers arrested a 14-year-old boy from Crawley on suspicion of attempting to cause grievous bodily harm, and with possessing a bladed article in a public place. He has since been bailed with strict conditions.
Anyone with information is urged to contact Sussex Police.