The incident occurred around 5.30 p.m. on Friday, July 15.

Three young men wearing balaclavas approached a 15-year-old boy sitting with a friend outside The Lynd Cross public house and Wilkinson’s store on West Street.

The boy was led around the corner to The Gym, and his bag was taken from him.

One of the three suspects was described as a 6’2″ slim white young man carrying a knife.

Members of the public witnessed what occurred and intervened, challenging the suspect and then bravely assisting in his detention in a nearby Waitrose store after a brief pursuit.

Police then apprehended the suspect.

The other two men were described as slim and black, standing 5’2″ and 5’4″ tall, respectively.

Officers have asked anyone who saw what happened or saw the three suspects together in the town centre to come forward.

Information can be reported to Sussex Police online or by calling 101, referencing serial 1144 of 15/07.

You can also call CrimeStoppers anonymously at 0800 555 111.

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