A ‘dangerous’ 17-year-old boy from Wembley who stabbed another teenager with screwdriver has been sentenced to 30 months’ detention today.

The youth, who cannot be named for legal reasons, repeatedly stabbed Anthony Knowles, 18, in Watford, in August last year.

Prosecutor Isabel Delamare told St Alban’s Crown Court the youth and a friend were on a train year when he began to stare at Mr Knowles.

When it reached Watford all three got off and Mr Knowles asked: “Is there a problem?”

The defendant said: “Come outside” and Mr Knowles replied: “Shut up.”

A friend picked Mr Knowles up outside the station and the youth waved the car down, leant inside the open passenger window and repeatedly stabbed Mr Knowles with the screwdriver, saying he was going to kill him.

Mr Knowles received stitches to wounds to his upper arm and back.

A doctor said the wound came close to puncturing a lung.

The police arrested the teenager in Wembley two days later.

He pleaded guilty to wounding Mr Knowles with intent and appeared for sentence via a video link from Feltham young offenders’ prison.

The youth has previous convictions going back to the age of 13.

Since being held on remand in Feltham he had knocked out a fellow inmate, caused two prison officers to be taken to hospital and had been found with an offensive weapon in his cell.

Sentencing the youth, Judge Andrew Bright QC said he had been found to be “emotionally detached” from what he does and was at a high risk of re-offending.

He told him: “I take the view he is dangerous and I hope that those responsible for his licence when he is released are aware of it. He needs a lot of support and help.”