Shoppers looked on in horror as a 12-year-old attacked a nine-year-old boy with a craft knife in Colchester town centre.

Passers-by in Sir Isaac's Walk came to the aid of the young victim, grabbing the blade-wielding youth and detaining him until police arrived.

Det Sgt Roy Clark, of Colchester police, said: "At about 4.55pm on Wednesday a young lad was attacked by another boy armed with a Stanley knife at St John's Wynd steps.

"The victim was not injured although his coat was slashed, causing about £20 damage."

Det Sgt Clark added: "I would imagine the victim was quite shaken. He was not injured but it is not a pleasant experience being attacked with a knife."

A 12-year-old Colchester boy was arrested and has received an official police reprimand by a duty inspector.

Under the new system introduced in April when giving reprimands police take into account all the circumstances, one of which is age. His details will be sent to the force's youth offending team.

A Home Office spokesman said: "Officers have discretion to issue cautions or reprimands for less serious offences. It is an operational matter for the force concerned."

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