Officers from Arun Police are seeking information relating to the incident in Linden Park.
A police statement on social media read: “We are concerned for the welfare of a boy who was seen being assaulted by a group of teenagers in Linden Park, Littlehampton, on June 13 around 6.20pm.
“If this was you, or if you have any information relating to this incident, report online or call 101 quoting 155 of 15/06.”
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