Police investigating the disappearance of Nicola Bulley have said all possible lines of inquiry to find the mother-of-two are being “exhausted”.
A team of 40 detectives are working on approximately 500 different lines of inquiry, Superintendent Sally Riley said.
More than 700 drivers who travelled through the village of St Michael’s on Wyre around the time the 45-year-old went missing are also being traced.
However, it is still the force’s belief that Ms Bulley fell in the River Wyre, Ms Riley added.
Giving an update at a press conference on Tuesday afternoon, Ms Riley, of Lancashire Police, said: “At the moment there are around 500 active pieces of information and lines of inquiry that we’re working on to try and find answers for Nicola’s family.
“This is normal in a missing person inquiry and does not indicate that there is any suspicious element to this story.
“The inquiry team remains fully open-minded to any information that may indicate where Nicola is or what happened to her.”
She added: “All possible lines of inquiry, search or investigation, are being exhausted.”
Ms Riley said: “It does remain our belief that Nicola sadly fell into the river and that this is a missing persons inquiry.
“Any information that comes in that indicates otherwise is being checked out all the time and negated as each inquiry comes up. We’re not closed in any way to any particular line of inquiry and we remain genuinely open to that.
“All these extensive inquiries however have so far not found anything of note.”
Family and friends of Ms Bulley have questioned the police theory that she probably fell into the water while walking her dog, after dropping her children off at school on January 27.
Specialist underwater divers are searching a stretch of river where police believe she may have fallen in.
Peter Faulding, a private search expert sometimes used by police, has said if his team cannot locate Ms Bulley in the river then she is not there and he would not rule out “third-party involvement” in her disappearance.
They have been concentrating on an area around and downstream from a bench where Ms Bulley’s mobile phone was left, still connected to a work call.
The lead to her springer spaniel dog, Willow, and its harness, were also left at the bench.
Police divers have previously searched the same area last week amid a huge ongoing hunt for mortgage adviser Ms Bulley, who lived in the village of Inskip, two miles from the river.
Police say they have ruled out Ms Bulley leaving that area of the river and suspect she may have gone into the water after an “issue” with the dog while walking.
