They've also released CCTV images of a man they want to speak to.
Teenage Girl Sexually Assaulted In Renfrew Park Attack
Police are looking for a man who sexually assaulted a teenage girl in a town centre park.
The 15-year-old victim was in Robertson Park, Renfrew, at about 10.45pm on Monday when a man started speaking to her.
He then sexually assaulted her before she left the park and contacted police.
The suspect is white, aged between 20 and 30, slim and with dark hair.
He was wearing blue jeans, a white t-shirt with a black and grey pattern and a black puffa-style jacket.
Officers are to carry out extra patrols in the area and detectives are keen to hear from dog walkers or anyone who may have been in the park on Monday night.
Detective Chief Inspector Filippo Capaldi said: ''Extensive enquiries are under way to establish the exact circumstances surrounding this incident and to trace the person responsible.
''Additional officers will be on patrol to provide reassurance to members of the public and I would like to speak to anyone who was in the park or surrounding area on Monday night.
''Perhaps you were out walking your dog or making your way home from somewhere? If you saw or heard anything suspicious or a man matching the description, please get in touch.
''Anyone with information can contact officers at the public protection unit based in Renfrew via 101 or alternatively Crimestoppers on 0800 555 111 where details can be given in confidence.''
It happened in Broxburn this morning.
It's after their Champions League qualifier.
Police say he suffered a serious facial injury and was taken to Edinburgh Royal Infirmary for treatment.
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