Alexander McDonald given 30 years for mother's murder Published duration 24 June 2015

image copyright Facebook image caption Alexander McDonald was found guilty of murdering his 57-year-old mother

A man who strangled and stabbed his mother in a frenzied attack while high on drink and drugs has been jailed for a minimum of 30 years.

Alexander McDonald, 27, also sexually assaulted Catherine McDonald, 57, at their home on 30 September 2014.

He was found guilty of murder at Exeter Crown Court on Tuesday.

Sentencing him, Mr Justice Dingemans said the attack was "an example of the destruction caused by the use of drugs in society".

The court heard McDonald, a waiter, had drunk alcohol at a wine-tasting evening at his work before taking cocaine.

He then embarked on a sex texting conversation with a male friend which left him "in a state of sexual excitement".

image copyright Avon and Somerset Police image caption Catherine McDonald was stabbed and strangled in her home in the Somerset village of Norton Fitzwarren

"I do not doubt that Mr McDonald would have not have acted as he did but for the ingestion of the drugs which disinhibited him," the judge said.

His mother, who had gained a first-class honours diploma in textiles, worked as a housekeeper at a care home.

Jurors were told he stabbed her with a kitchen knife, a knitting needle and scissors as she slept in her bed.

He also wrapped a power cable round her neck twice before pulling it tight.

After killing her - and after a futile attempt to clean up - he took her bank card and car and fled. But he crashed the car near Tiverton, Devon, and was quickly arrested.

McDonald showed no emotion at the verdict and held his head in his hands as the 30-year jail term was announced.

The judge said after that time had been served there was no guarantee that he would be freed.