Prosecutors have failed to convince appeal judges to jail a thief who received a non-custodial sentence for repeatedly stabbing a shop worker.

Kenneth Graydon, 40, received a community payback order after judge Lord Turnbull heard heard how he attacked Frieda Young, 61, in November 2014.

The High Court in Glasgow heard how Graydon was suffering from serious mental health issues at the time of the crime.

The court heard how Graydon walked into the Spar shop in St Quivox Road in Prestwick, Ayrshire, and stole groceries and tobacco worth £19.51.

Mrs Young then chased Graydon into the street following the incident. But he pulled a knife from the waistband of his trousers, stabbed Mrs Young and left her in a pool of blood at a nearby bus stop.

Graydon, also of Prestwick, admitted stabbing Mrs Young to her severe injury and permanent disfigurement.

However, Lord Turnbull put Graydon on a community payback order for three years under which he is being supervised by the authorities.

He also has to undergo mental health and rehabilitation treatment.

Speaking after the case, Mrs Young told a newspaper: "I honestly cannot believe this, it's absolutely atrocious. "This is soft justice in the extreme and I want Crown Office prosecutors to appeal it.

"Everyone who knows me in Prestwick is shocked."

On Friday, Crown Office lawyers went to the Court of Criminal Appeal in Edinburgh to ask appeal judges Lord Carloway, Lord Bracadale and Lady Dorrian to quash the sentence.

Prosecutors want the appeal court judges to send Graydon to jail.

On Friday, advocate depute Iain McSporran told the court that Mrs Young had been traumatised by the attack.

He said that given the circumstance of the offences, judges would be entitled to quash the sentence and impose jail time on Graydon.

He added: "We believe the judge is in error."

Defence counsel Lorenzo Alonzi told the court that his client had long standing mental health issues.

He said Graydon had been released from a psychiatric unit just a month before the incident. Mr Alonzi said that given the state of his client's health, the sentence was appropriate.

The appeal judges told the lawyers that they would issue the reasons for their decision at a later date.

But Lord Bracadale said the appeal judges decided that the sentence imposed by Lord Turnbull was "robust" and that the public had sufficient protection from Graydon harming them.

He also said that should Graydon re-offend it would be open to the court to sentence him for breaching the order.