Detectives investigating the attack in Swinegate, Grantham, last Sunday (September 14) are appealing for the public's help to trace the man.

The attack happened at around 9.40pm as the victim was walking alone.

The man approached her from behind, held her at knifepoint and subjected her to a sexual assault.

He was captured on CCTV walkling through St Wulfram's churchyard as he left the scene.

The footage shows him walking with a distinctive gait, which police believe could be the key to him being identified.

DC Amy Lovell said: "We have decided to release this footage in the hope that members of the public who know the suspect or who saw him at any point during the night will come forward and help us with our enquiries.

"The most striking element of the footage is the distinctive gait of the suspect.

"It is possible that he has concealed the knife in his trousers and this is causing him difficulty in walking, or he has a pronounced limp that would be instantly recognisable to anyone who knew him or had seen him."

The suspect is described as Chinese, in his late teens to early 20s, 5ft 5ins, with short, dark, slightly spiky hair and acne scarring on his cheeks.

He wore a dark green beanie hat and a dark coloured waist-length jacket made out of waterproof material. The jacket was zipped up to the neck and had an emblem or motif on the back.

The knife he used had a seven-inch blade and a four-inch black handle with three silver dots on it. It has not been recovered.

Police believe the male could have been seen in the Castlegate, Manthorpe Road, Brook Street, Avenue Road or St Peter's Hill areas of town before and after the attack and are urging the public to come forward with information.

DC Lovell said: "We need people to come forward with information as a matter of urgency.

"Someone living in the local community will know who this male is or will at least have seen him that night.

"If you saw him or have any information on him, no matter how insignificant you think it might be, please get in touch.

"This knid of sexual assault involving a weapon is very rare in Grantham. It is a safe town and there is no need for any panic.

"But, as always, we would urge women in particular to take common sense precautions. Don't walk home alone at night and always stick to well-lit well-populated areas."

Information to DC Amy Lovell on 01476 402222, ext. 3356

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