A Lancashire TV aerial fitter who sexually assaulted an 85-year-old woman in her own home after doping her with designer drugs has been told he faces a "lengthy custodial sentence".

A jury took just more than a hour to convict Darren Penfold, 48, of the attack and also administering a substance with intent to overpower the pensioner to engage in sexual activity.

The workman from Cleveleys, slipped Class C controlled drugs BZP and TFMPP into her glass of whisky.

Preston Crown Court heard the woman said she came round on her bed the following morning not fully clothed and had no recollection of how she got upstairs.

Police were called when she began to remember that a man had abused her.

She reacted angrily under cross-examination from counsel for Penfold at the trial this week.

She broke down in tears as she told the jury: "I was fighting in the war for this country.

"I met people of all nationalities. Everyone was kindness itself.

"I am not used to anyone like that man (Penfold). I have never known anyone like that man.

"He has altered my whole life. I do not recognise myself as the same person.

"I used to trust anyone."

Following the verdicts, Judge Pamela Badley said: "It is clearly a very grave matter.

"This is going to be a lengthy custodial sentence."

She remanded the father-of-three in custody as she ordered pre-sentence reports and said she would particularly look at the findings regarding the dangerousness of the defendant.

Giving evidence, Penfold said he was "absolutely mortified" when the allegations were first put to him by police.

"To this day I can't get over being accused of doing that to somebody," he said.

The jury rejected his account, though.

Penfold was also found guilty of stealing four bottles of alcohol from the woman's home in Blackpool.

Addressing the jury, Judge Badley said: "This has not been a pleasant case for you.

"I thank you for your patience and hard work you have undertaken."

Penfold returned to the house on the night of the incident on January 27 last year on the pretence of volunteering to move the woman's old television.

He had been doing ongoing work at the property since before Christmas but had initially botched the aerial fitting and his victim was left with no television signal over the festive period.

Forensic examination showed the defendant's DNA was found on the victim's underwear, while her DNA was on nail scrapings and finger clippings taken from him.

Penfold argued that he had brushed against her underwear while earlier working in her bedroom.

He claimed he never went upstairs on the night of the attack and had no explanation as to how the drugs had found their way into the woman's daily tipple of Southern Comfort.

The court heard that a urine sample was taken from the victim - who was 83 at the time - which showed a significant amount of alcohol had been taken in the period concerned and traces of the drugs which were marketed as legal highs until December 2009 when they were outlawed.

Self-employed installer Penfold, of North Drive, who has worked across the North West for 25 years, had denied all the offences.

He had no previous convictions for offences of this kind.

He showed no emotion as he was led away from the dock.

Sentencing will take place on October 10.

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