A 39-year-old man on trial accused of grooming a 13-year-old Bradford schoolgirl for sex had a conviction for indecently assaulting another girl of the same age in 2003, a jury has been told.

Shabir Ahmed, who denies having a sexual relationship with the orthodox Muslim girl and indecently assaulting her adult sister, was on the sex offenders’ register after admitting molesting the girl in his vehicle 11 years ago.

A police computer expert found that attempts had been made on his laptop computer to call up his name on the register.

Images of child pornography were found on the machine when it was seized by the police last year, prosecutor Caroline Wigin told Bradford Crown Court yesterday.

Ahmed, who lived in Windsor Court, Little Horton, Bradford, before moving to Newcastle, denies sexual activity with a child under 16, sexual grooming, sexually assaulting a woman in her 20s and attempting to pervert the course of justice.

He also denies nine charges of possession of indecent photographs of a child.

Miss Wigin alleges the defendant threatened to petrol bomb the older sister’s home and to put explicit film of his sex with the schoolgirl on the internet if anyone was told about his relationship with the schoolgirl he met in Lister Park, Manningham.

The jury was told that the girl’s sister and her aunt saw Ahmed having sex with her.

Ahmed told the police he had never had a sexual relationship with the girl or indecently touched her older sister.

He said other men had access to his laptop computer and he had no knowledge of the indecent images of young girls police found on it.

He used the machine to look at pictures of pigeons and to watch Indian movies.

Ahmed said he met the sisters by chance in the park and chatted to them after they looked over at him.

The older woman became his friend and he often gave her lifts in his car.

Both sisters had been to his Bradford flat on a few occasions but the schoolgirl had never been with him there alone.

The trial continues.