The attack took placeat around 5pm (Sunday, 20 November).
The boy, aged 13, was sitting in the bus, parked at the bus stop in Kendal Avenue at the junction with Cuckmere Lane, when a glass bottle was thrown by a group of youths at the window next to him.
This caused the window to break, and the boy suffered facial injuries from the shards of glass.
A 13-year-old boy from Southampton has been arrested on suspicion of causing grievous bodily harm with intent and criminal damage to property valued under £5,000 and was bailed while enquiries continue.
Sgt Loraine Stockham from Southampton West Neighbourhoods Policing Team said:
“We believe the victim and the group were known to each other and that this was an isolated incident.
“We know there were a number of witnesses so I would encourage them to contact us with any information or mobile phone footage they might have.
“Similarly, if anyone has dash cam, CCTV or ring doorbell footage, please get in touch.”
Call us on 101, or report on the police website quoting 44220471656.
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