A persistent sex offender from Auchinleck who preyed on vulnerable females during two decades of abuse has been jailed for 12 years.

Hugh Derby (52) targeted three of his victims when they were asleep and under the influence at the time of his sex attacks.

He took part in the gang rape of a 15-year-old girl at a flat in Main Street in Auchinleck after she was intoxicated with drink and drugs.

A judge told Derby at the High Court in Edinburgh: "You have been convicted by the jury of grave and serious charges."

Derby, formerly of Cameron Drive, Auchinleck, had denied a series of charges during an earlier trial - but was convicted of four offences of sexual assault, one of sexual activity towards an underage girl and one of indecent assault and rape.

He claimed that some victims had consented, and that on other occasions the offences did not take place at all.

But judge Thomas Welsh KC said jurors had disbelieved Derby's version of events in his evidence.

The judge pointed out that three of those who were subjected to abuse by Derby were asleep or incapacitated at the time.

He said: "You clearly acted in a premeditated and predatory manner, identifying and isolating your victims when they were most vulnerable and unable to resist your approaches."

The judge said that one woman was attacked by Derby in 2013 while on a camping expedition at the Leadhills, in Dumfriesshire.

She awoke in a tent in the middle of the night to find him beside her carrying out a sex act.

The judge said: "These were all shocking violations of the sexual autonomy of  your victims."

Mr Welsh said that Derby's conduct to further victims was both "predatory and harmful". He said he had read victim impact statements detailing the psychological impact of his offending.

The judge told Derby that in addition to the 12-year jail sentence, he was ordering that he should be monitored for a further three year period.

During that time he will be subject to supervision by police and local authority officers and can be returned to prison if he breaches licence conditions.

Derby began his offending in 2000, when he took part in an indecent assault and rape of the 15-year-old girl in Auchinleck with others.

In 2011 he targeted another victim for an attack in Auchinleck and removed her lower clothing before carrying out a sex act on her.

Two years later he sexually assaulted a 12-year-old child in the town and grabbed her, struggled with the child and lay on top of her before kissing her and pressing himself against her.

He later molested the girl again when she was aged 15, at a Calvin Harris concert at Bellahouston park in Glasgow in August 2015.

His final victim was subjected to a sexual assault at an address in Auchinleck in 2019 when Derby scratched her back and squeezed her buttocks.

One woman, who woke up on a couch to find Derby abusing her, said: "I kicked out. I wanted to kill him. I couldn't believe he would hurt me like he hurt me." 

Defence counsel Ian Duguid KC said it was "inevitable" that Derby would face a prison sentence following his convictions.

He said Derby has no record for sexual offending, although he has previous convictions for assault.

The defence counsel said: "He does intend to engage, as he may be required to to do, in addressing his offending behaviour."

Derby was told he would be placed on the sex offenders' register indefinitely following his sentencing.