A 15-year-old boy who swore at a police officer and said “I hope you die” during unrest in Whitehall has been discharged by a judge who told him: “Please don’t come back to court again.”

The teenager, from Kent, was arrested as officers tried to disperse the crowd who were present at the Enough is Enough protest in central London past 8.30pm when protesters were ordered to leave on July 31.

The boy put his middle finger up to police officers and called one of them a “prick”, Sevenoaks Youth Court heard.

Prosecutor James Nichols said that when the teenager was arrested there was a struggle and he told a police officer: “I hope you die you c***, watch what I do when I get through here.”

At court on Friday, the boy pleaded guilty to using threatening or abusive words or behaviour and was conditionally discharged by the judge for nine months and ordered to pay £105 in court and victim costs.

Asked why he attended the protest, the youngster, who just finished school, said: “Because against knife crime because three girls were killed in Southport.

“We thought it would be a peaceful protest.”

The court heard in mitigation that the boy had never been in trouble before and was very sorry about the incident, and that being in custody was a “devastating experience” for him.

District Judge William Nelson told him: “You made a very, very foolish decision to take part in this protest, this protest was not what the organisers led you, who participated in it, to believe it was.

“What it became frankly outside the Houses of Parliament and into Whitehall was a disgusting display of racism and violence.”

The judge added he did not consider the teenager as part of the main group of offenders but instead was “completely carried away as a 15-year-old in among a group of men who frankly should have known better”.

He said: “As a result you behaved in a way I have no doubt you would not have normally behaved in.

“Please don’t come back to court again, it’s really not somewhere you really want to be.

“Go and enjoy college and get on with your life.”