A 30-year-old woman has been indecently assaulted in East Kilbride, South Lanarkshire.
She was grabbed from behind by a man as she walked her dogs in the Greenhills area at about 2010 BST on Monday.
The attack happened in woods near Newlandsmuir Road and Troon Avenue.
Police described the assault as "very frightening" and said the suspect may have injured his hand during the struggle.
The woman had seen a man with his T-shirt pulled up covering part of his face.
He then followed her as she made he way up a footpath, grabbed her and indecently assaulted her.
After a struggle she managed to break free and the attacker fled towards Troon Avenue.
He was described as white, aged between 18 and 20, about 5 ft 11in tall, with a slim build and light brown hair.
He was wearing dark coloured jogging trousers and his T-shirt was also dark coloured.
Det Con Daniel Coyle from East Kilbride CID said: "This was a very frightening experience for the woman and she is very upset by the ordeal. It's imperative we trace this person and it may be that someone was in the area at the time of the incident.
"The area is well used by the community and it's possible people were out and about, perhaps walking their dogs.
"I would urge anyone who may have been in the area at the time to get in touch, even if they think the information they have is insignificant, it could help up us trace the man responsible for this assault."