A new police unit celebrated an early success on Thursday when a robber, who held a knife to the throat of a woman who was giving him a lift, was sent to prison.

Leigh Cooper, 20, of Wharton Road, Headington, Oxford, was sentenced to three years in prison at Oxford Crown Court after denying robbing Melonie Brook on August 9.

It was one of the first convictions secured by a CID unit set up in June to investigate robberies in the city.

Jill Hurworth, prosecuting, said Cooper, a habitual heroin and crack cocaine user, robbed Ms Brook of £140 and a mobile phone after she offered him a lift in her Fiat Uno.

They had met at the house of a mutual friend, Kimberly Jones, of Barton Road, Headington.

Ms Brook agreed to give Cooper a lift to Harrow Road, but Cooper directed her to an isolated road, held a knife to her throat and demanded the money.

He ran away but was found by police an hour later hiding in some trees near Wick Lane, Barton.

Rachael Drake, defending, said Cooper committed the crime because of his need for drugs but was determined to kick the habit and train as a carpenter.

Dc Justin Gosling, of Oxford Police's new robbery team, said: "The most important thing is the service to the victim. The victim was extremely scared and scared of giving evidence and I hope the success of this case puts her mind at ease."