Police in the UK investigating the disappearance of mother-of-two Nicola Bulley want to trace a "key witness" who was seen pushing a pram in the area near where the dog walker went missing.
In a statement published on Facebook, Lancashire Police said that the woman was seen on Garstang Road/Blackpool Road, St Michael's, on the morning of 27 January pushing a pram.
Police believe that the woman may have walked along the river path where Ms Bulley went missing.
"Officers leading the search for Nicola Bulley, who is missing in St Michael's on Wyre, need to trace a key witness who they believe was in the area on the morning of Nicola's disappearance.
"A woman was seen walking on Garstang Road/Blackpool Road, St Michael's on the morning of Friday January 27 pushing a pram.
"She was seen walking from the direction of Allotment Lane towards The Grapes public house at approximately 8.22am and is seen again walking on Allotment Lane towards Garstang Road at 8.41am.
"It is believed that the female in question may have walked along the river path during these times and so detectives want to speak to her and urge her to get in touch.
"We are also appealing to anyone who was driving down Blackpool Lane/Garstang Lane on the morning of Friday January 27 between the times of 9am and 10am who has dash cam footage on their vehicles to make contact."
Police believe the 45-year-old mortgage adviser went missing in just "a 10-minute window" while she was walking her dog, Willow, close to the River Wyre, after dropping off her daughters, aged six and nine, at school.
Ms Bulley had logged in to a Microsoft Teams call at 9.01am, which ended at 9.30am with her phone still connected to the call. She was seen by another dog walker at 9.10am (the last known sighting) and police traced telephony records of her mobile phone as it remained on a bench overlooking the river at 9.20am.
The device was found by a dog walker at around 9.35am, with Willow nearby.
It comes as search teams from Lancashire Constabulary are continuing to trawl the River Wyre near St Michael's, working on the hypothesis that the woman from nearby Inskip, could have fallen in.
However, Ms Bulley's family and friends have questioned that police theory.
In a Facebook post, Ms Bulley's sister, Louise Cunningham, urged people to "keep an open mind" as there is "no evidence whatsoever" that the dog walker fell in the river.
"Not all CCTV and leads have been investigated fully, the police confirmed the case is far from over."
Ms Bulley's friend, Emma White, also cast doubt on the police theory, telling Sky News it was based on "limited information".
"When we are talking about a life we can't base it on a hypothesis - surely we need this factual evidence," she said.
"That's what the family and all of us are holding on to - that we are sadly no further on than last Friday. We still have no evidence, and that's why we're out together in force."
In an interview with The Sun, Ms White said that police were working to get data off Ms Bulley's Fitbit watch.
"The Fitbit had not been synced since Tuesday," she said.
"The police are trying other ways to try to get information from it."
The police search has been aided by specialists and divers from HM Coastguard, mountain rescue, and Lancashire Fire and Rescue Service with sniffer dogs, drones and police helicopters deployed.
Detectives are also working behind the scenes to analyse CCTV and dashcam videos, and members of the public with footage which could be useful have been urged to come forward.