A desperate teenage drug addict who launched a brutal street attack on a disabled pensioner has been locked up by a judge today.

Frantiska Kinacova, 18, put her head in her hands as a Czech interpreter explained to her that she was being sent to a young offenders' institution for two years and eight months after she attempted to rob 73-year-old Roy Cook after he had visited a Bradford city centre cafe for his breakfast.

Mr Cook, who suffers from brittle bones in his back and walks with the aid of crutches, was targeted by heroin-user Kinacova as he left the Northgate Bistro at about 8am on June 9.

Bradford Crown Court heard how Kinacova, who came to the United Kingdom when she was seven, was living on the streets and desperate to feed her heroin habit when she tried to grab Mr Cook's wallet, knocking him to the ground.

Prosecutor Michael Smith said the victim, who also has a pacemaker and a metal plate in his leg, described his attacker as ''coming at him like a bull'' before feeling a blow to his face and kicks to his body as he lay on the ground.

A member of staff from the cafe witnessed the attack and described how Kinacova kicked out at their customer and ''ragged him around'' as she tried to find something to take from him.

The court heard how public-spirited John Lambert also saw the attack and he intervened to help the pensioner.

Mr Smith said Mr Lambert grabbed hold of Kinacova, but during a lengthy struggle with her she bit him on his arm.

The bite was severe enough to break Mr Lambert's skin and the injury bled, but he was able to hold onto the teenager until the police arrived.

Mr Cook suffered a cut to his eye, bruising to his face and his back was particularly painful.

''He said he had had nightmares about the assault but medically he had been given the all in due course,'' said Mr Smith.

Judge Colin Burn noted that Mr Lambert had shown remarkable bravery in intervening and should be given significant credit.

Kinacova, who pleaded guilty to the attempted robbery charge, was said to have left school at 16 with few qualifications and had never been employed.

A psychological assessment of her suggested that she had some learning difficulties and her barrister Niall Carlin told the court that she was in the grip of a terrible heroin addiction at the time of the offence.

The court heard that the teenager had no previous convictions, and Mr Carlin said the attempted robbery had been an opportunistic offence.

Mr Carlin said his client had expressed remorse for the incident, but Judge Burn said Kinacova had been desperate to get money at any cost when she attacked Mr Cook.

Judge Burn said: 'It was a brutal attack on a vulnerable man.''

Kinacova was sentenced to 32 months in a young offenders' institution for the attempted robbery with a concurrent eight months in custody for resisting Mr Lambert as he tried to detain her.