A WOULD-BE thief was thwarted by have-a-go heroes inside a discount store.

Witnesses described seeing a customer and shopkeeper tackle the teen to the ground as he tried to steal from the Bargain Buys store in London Road, Brighton, on Tuesday.

Armed police were called to the shop shortly before 9pm to reports of a man trying to steal and making threats to a staff member when challenged.

It is understood the shopkeeper held the culprit in the store until police arrived.

Officers were told he was carrying a knife, but no weapon was recovered from the scene.

A Sussex Police spokesman said: β€œAn 18-year-old man from Guildford was arrested on suspicion of robbery and remains in custody for questioning. Anyone with information can report online or call 101.”