AN ALEXANDRIA man sexually assaulted a woman in the street - before being chased off by her hero boyfriend.

Steven Shillan pounced on the 34 year-old stranger as she walked through the town in May this year.

The 21 year-old fiend told his victim: “I am going to rape you.”

The High Court in Glasgow heard earlier this week how the victim's boyfriend happened to be nearby and spotted what was happening.

Prosecutor Mark McGuire said: “He shouted: 'Get off her. What the f*** are you doing?'.”

Shillan - a groundskeeper - then got up and fled the scene.

However, he was later snared after the woman's blood was found on his jeans and trainers.

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Shillan is now behind bars after he pleaded guilty on Tuesday to a charge of sexually assaulting the victim with intent to rape.

He will be sentenced next month.

The court heard how Shillan grabbed the woman and assaulted her as she walked near Alexandria's Argyll estate.

He put his arm around her neck before punching and kicking her as well as stamping on her face.

Mr McGuire said the force was such, that his footprint was “clearly visible” on the woman.

The hearing was told the victim was left in “no doubt” what Shillan planned.

As he continued the attack, the bleeding woman yelled and tried to stop Shillan from sexually assaulting her.

Her terrifying attack only ended when her partner arrived on the scene.

The woman was described as “hysterical” with her face covered in blood.

She was later treated for bruising and swelling, but fortunately suffered no fractures.

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Mr McGuire added: “The attack has had a profound and continuing effect on her.”

Shillan was recognised from CCTV footage of the area at the time.

He made no comment when held – but forensic evidence later tied him to the attack.

Lord Boyd remanded him in custody as sentencing was deferred for reports.