A Bristol who robbed an 80-year-old woman at knifepoint and burgled another family to fund his crack cocaine habit has been jailed for six years.

Aissam Zbili was a skilled anaesthetic nurse who was highly regarded by colleagues at North Bristol NHS Trust.

But Bristol Crown Court heard that, following his divorce in 2004, he became addicted to the Class A drug and resorted to crime to fund his fixes.

Zbili, 46, of Fishponds, pleaded guilty to robbery and two aggravated burglaries, which all took place in November last year.

Imposing sentence Judge David Ticehurst told him: "It is a perfect illustration of the nightmare an addiction to Class A drugs can create.

"You were a professional, highly qualified anaesthetic nurse and your descent into chaos began in 2007, when a friend introduced you to crack cocaine."

Zbili was told he would serve half of his sentence in custody, followed by deportation.

Giles Nelson, prosecuting, said it was on Bonfire Night last year when Zbili turned up at a home in Gloucester Street, Eastville, holding a knife, and demanded "give me all the money you made" from unemployed mum-of-two Kadine Sutherland.

Mr Nelson said: "She was on benefits and she got £100. She gave it to the defendant and he left.

"Police were called to the scene, there was forensic analysis and the defendant's fingerprint was found on a door."

The court was told that, later the same night, Zbili returned to the address with a knife and again asked for money but left empty-handed.

A police scenes of crime officer recovered Zbili's DNA from his saliva found at the home.

Mr Nelson said that although Zbili claimed he knew the family, the prosecution did not accept he did.

However, he said that Zbili had befriended retired police officer June Long, 80, and she had lent him money before he turned up at her flat, grabbed a knife from her kitchen and put it to her throat – helping himself to a further £140.

The court heard Mrs Long died in January, but there was no established connection between the robbery and her death.

Nicolas Gerasimidis, defending, said while once his client had been a hard-working anaesthetic nurse, he divorced, due to pressures of work, and lapsed into drug addiction.

He said his client maintained he did know the victim of the aggravated burglaries.

He was bitterly remorseful that he had robbed a kind elderly woman.

Mr Gerasimidis told the court: "The defendant was a drug addict and in debt to drug dealers.

"He says he was threatened with his life, he went to borrow money from Miss Long and she didn't lend him any.

"That made him pick up the knife and threaten her with it. He accepts threatening her, but not holding the knife to her throat."

Detective Constable Tania Coles said: "The victim is satisfied with the sentence he has been given and hopes to put this behind her."