A single mother was subjected to an hour-long sex attack at knifepoint after a bogus official conned his way into her Bradford home.

Detectives today described the attack as horrendous and say the 36-year-old woman has been left severely traumatised by her ordeal.

The woman was watching television at her home in the Holme Wood area of Bradford when the attacker knocked at her door claiming to be from the council's Social Services department.

Once inside he started questioning the victim about her seven-year-old son, who was sleeping upstairs.

When the woman became agitated he pulled out a knife and subjected her to a serious sexual assault.

He threatened her verbally and physically throughout the hour-long attack, holding the knife to her throat and face.

As he left the property he threatened her again, telling her that if she reported the incident to police he would find out and come back.

Detective Sergeant Billy Murdoch, of Odsal CID, said: "This was a horrendous and sustained planned attack on a lone parent.

"The woman was frightened for her life and the safety of her son. She is severely traumatised and receiving counselling.

"We are not sure whether the attacker left on foot or in a vehicle. Officers have carried out house to house inquiries in the area and I would urge anyone with information to come forward as soon as possible."

The incident happened at about 10.30pm on Tuesday, February 1 but the woman has only just come forward.

The attacker is described as white, aged about 50, over 6ft tall, clean shaven, with blue/green eyes, dirty blond hair which was short at the sides and spiky on top, and an athletic physique.

He was wearing a multi-coloured woolly jumper and multi-coloured three-quarter-length duffle coat with toggle fastenings, cream chinos and blue suede shoes.

He is believed to have a skin allergy on one of his hands and an old scar on his left cheek. The knife appeared to have ornate carving on its dark brown handle.

Witnesses or anyone with information which may identify the attacker are asked to contact Odsal CID officers via the help desk on Bradford 376659 or 0845 6060606.

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