A paedophile who claimed he poured bleach on his genitals to stop him abusing boys has admitted molesting three teenagers.

Service engineer Allan Fraser admitted the offences, which were committed over the course of 12 years between 2004 and 2016, when he appeared at the High Court in Glasgow on Friday.

One boy described being "frozen with fear'" as the 41-year-old sexually abused him.

He said Fraser went on to regularly abuse him when he was meant to be babysitting him.

The sex offender, of Great Western Road in Aberdeen, also abused the boy at a garage in an industrial estate in the city.

Prosecutor Ian Wallace said: "The boy did not want to do any of this but he did not know how to stop the accused. He was scared of him.

"He says this abuse has had a significant emotional effect on him. It has affected his confidence and relationships."

Fraser abused a second boy when the victim was aged between 14 and 16 and also showed him pornographic videos.

The court heard the abuse on the third teenager started when he was 13. On one occasion the accused asked the boy to send a photograph of his private parts.

The offences were committed at various addresses in Aberdeenshire.

Mr Wallace said: "The abuse has had a significant impact of this boy. He is undergoing counselling and therapy."

The prosecutor added: "The accused said he had been pouring bleach on his penis and cutting his penis to prevent his sexual urges and to stop him abusing."

Lady Scott deferred sentence on Fraser and ordered a risk assessment to gauge the danger he poses to children.

He will be sentenced next month.