A forensic search expert brought in by the family of Nicola Bulley to help find her says he was "not tasked to search the reeds" where a body was pulled from the water on Sunday 19 February.
Peter Faulding's team from Specialist Group International (SIG), were brought in to look for Ms Bulley ten days after she went missing while walking her dog along the river in St Michael's on Wyre in Lancashire.
Speaking on ITV's Good Morning Britain, Mr Faulding said his team's task was to clear the river and at the time of his search, there was no body in the river.
He said: "Our search was not in the reeds, our main focus was above the bench area.
"I can hand on heart say we did our best, but she was not on the river bed, we would have seen her clearly."
The team from SIG stopped their search on Wednesday 8 February, after Mr Faulding said Nicola was "categorically not" in the area of the river where police believe she fell in.
Speaking to ITV Granada Reports that day, Mr Faulding said:
"We've done very thorough searches all the way down to the weir. Police divers have dived it three times, extremely thoroughly.
"If Nicola was in that river I would have found her - I guarantee you that - and she's not in that section of the river."
The investigation into Nicola's disappearance has attracted widespread speculation as well as criticism of the police response.
Lancashire Police came under fire after making Ms Bulley’s struggles public.
In a press conference on Wednesday 15 February, they revealed the mother-of-two was classed as a "high-risk" missing person immediately after her partner Paul Ansell reported her disappearance, "based on a number of specific vulnerabilities".
The force later added in a statement that Ms Bulley, from Inskip in Lancashire, had stopped taking her HRT medication.
A public backlash and interventions from both the Government and shadow home secretary Yvette Cooper followed, with Lancashire Police confirming a date had been set for an internal review into the investigation.
A police spokeswoman said: "A review of the investigation is diarised and will be conducted by our head of crime Detective Chief Superintendent Pauline Stables."
Mr Faulding said Lancashire Police should not have withheld personal information about Ms Bulley, telling Good Morning Britain that it would have "maybe changed his search strategy".
He said: "I think there were a lot of egos playing out.
"I think people didn't want us to come on board."
Lancashire Police say they are in the process of formally identifying the body recovered from the river Wyre and that Ms Bulley's family are being kept updated.
In a message to Sky News, her partner Paul Ansell said: "No words right now, just agony.
"We’re all together, we have to be strong."
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