Police looking into the disappearance of Nicola Bulley say they were made aware of a 'number of specific vulnerabilities' which were crucial in the early stages of their investigation.
During a press conference at Lancashire Police HQ, senior detectives said they have still not received a 'single piece of evidence' to suggest the missing mum was a victim of crime.
Speaking at the briefing, Senior Investigating Officer Detective Superintendent Rebecca Smith, said her main working hypothesis is that the mum-of-two went into the river.
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She said that as soon as Nicola was reported missing, following information provided by her partner Paul, and based on a number of specific vulnerabilities they were made aware of, Nicola was graded as a high-risk missing person.
"That is normal in a missing person investigation with the information we were in possession of," she said. "As any senior investigating officer does, you form a number of hypotheses, that is scenarios which are possible from the information to hand.
"Those hypotheses included the one that she possibly could have gone into the river, that there could have been third-party involvement and lastly, that she could have left the area voluntarily.
"Those hypotheses have remained in place throughout, are reviewed regularly. At the initial stages based on the information I received, I made it clear that it was my working hypothesis at that time based with all the facts that the main hypothesis I was working on at that time was that Nicola had gone in the river."
Supt Smith refused to give more details when asked about the specific vulnerabilities they were referring to. Referring to Ms Bulley’s partner Paul Ansell, she told a press conference: "It’s normal in any missing person investigation that you obviously gather as much information at an early stage about the person in question, which is no different and we did that with Paul.
"I’m not going to go into the details of those individual vulnerabilities. I’ve asked you to respect the family, who are going through unimaginable pain and distress at this moment.
"But those vulnerabilities based our decision-making in terms of grading Nicola as high risk and have continued to form part of my investigation throughout."
Asked if she hoped to find her alive, Det Supt Smith said: "I hope with all my heart that we find Nicola Bulley alive more than anything."
Assistant Chief Constable of Lancashire Police, Peter Lawson, told the press conference he and his team were revealing more information than usual, due to the extremely high level of media and public interest in the case.
Speculation about what might have happened to Nicola has continued to grow in the 19 days since she vanished while walking her dog in St Michael's on Wyre on January 27.
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