By Dave Finlay

A HIGH-risk sex attacker who pounced on a school teacher in broad daylight and subjected her to a terrifying assault was jailed for four and a half years today.

John Burns, 28, had been consuming "legal high" drugs before carrying out the attack on his victim whom he intended to rape.

Burns tried to cover her mouth with his hand as she repeatedly shouted "No please don't" after he pinned her to the ground and warned he had a knife.

He will be on the sex offenders' register for life.

A judge told Burns: "You set upon your victim in an open location, visible from and surrounded by housing and busy roads."

Judge Craig Scott QC said at the High Court in Edinburgh that the attack occurred in circumstances where the victim was entitled to have felt safe.

The judge said the attack had had profound effects for the victim and added: "She is continually on her guard. She has been traumatised by a sustained and intimate sexual assault."

He said he accepted that Burns had significant mental health problems but added: "I was advised the difficulty so far as the attack was concerned arose through your involvement in the use of legal highs."

He pointed out that a background report prepared on Burns had assessed him as posing a high risk of further sexually aggressive behaviour.

The judge said he would have jailed Burns for five years if he had been convicted of the crime after trial.

He also ordered that Burns be kept under supervision for a further two years and warned that if he breached the conditions of his licence during that period he could be returned to custody.

Burns earlier admitted sexually assaulting the woman with intent to rape her at an area between Invercanny Drive and Cally Avenue, Drumchapel, on May 11, 2015.

The court heard the woman was walking alone towards Drumchapel train station when the attack occurred.

Advocate depute Paul Brown said Burns launched his attack on her from behind and bundled her to the ground before he lay on top of her and pinned the struggling woman down.

At one point in the assault he told her: "Keep quiet. Keep still. I've got a knife." He pushed the woman's skirt up as she kept saying: "Please don't." Burns responded: "Just let me do it then."

Mr Brown said the victim was terrified and told her attacker: "I need to go to the hospital to see my dad." The remark stopped Burns in his tracks and he asked her: "Really?"

He abruptly stopped the sex attack and his victim watched him running away unsure whether he would return. She arrived at Drumchapel police station in "an extremely distressed state".

DNA testing was carried out on clothing from the victim and after a check with a DNA database was carried out a match for unemployed Burns was returned.

A search of Burns home in Drumchapel recovered a pair of glasses which fitted the description of the victim of the spectacles worn by her attacked.

Defence counsel Frances Connor said Burns had committed a "spur of the moment" assault without any planning.

She said he is a schizophrenic and added: "The difficulty appears to have been his involvement in taking legal highs and substances."

Ms Connor said he had been placed on suicide watch in prison and added: "His remorse is such that he has somewhat lost the will to live."

Burns was earlier placed on the sex offenders' register and he will remain on it indefinitely.