Police trying to identify a woman who was found dead in an Oxfordshire lake have released CCTV images in an appeal for help.
Officers were called to Cresswell Lake, between the A40 and A34 near Yarnton, just before 8.30pm on 16 August, where they discovered the victim.
A post-mortem examination was carried out last Friday but police said it failed to establish the cause of her death, which is being treated as unexplained.
Detective Inspector Tracey Benham said: "Despite extensive investigations, we have exhausted lines of enquiry as to identifying the woman, and so we are taking the decision to release these CCTV images, captured on 8 August, as we have ascertained that this is very sadly the woman who was located in the water."
She said there have been no missing person reports in the Thames Valley of a woman matching the description.
The woman is believed to be aged in her mid-twenties.
Police described her as light-skinned and about 5ft 6in tall, with a slim to medium build.
She was wearing an olive green Barbour jacket, a burnt orange jumper, an orange-red and cream striped long-sleeved t-shirt and fitted blue jeans.
Officers have been told there was a woman in the area knocking on doors and asking for a shower, and they believe this could have been the victim.
Members of the public have been urged to contact police if they have any information that could help them with their investigation.
"This is a tragic incident and we are determined to find out who the deceased person is and are leaving no stone unturned in our efforts to identify her and notify her next of kin," Det Insp Benham added.
She said: "I would ask anybody with any information, no matter how insignificant you believe this may be, to contact 101, or make a report online quoting incident reference 2048 (16/8)."