A second witness has come forward to say they also reported a "shabby red van" near where Nicola Bulley went missing.
The mortgage adviser, 45, was last seen two weeks ago walking her dog Willow near the River Wyre in the small village of St Michaels on Wyre, Lancashire.
The mum-of-two's phone was found on a bench by the waterside and had recently connected to a work call.
Police have launched an extensive search of the area and said their "main working hypothesis" was that she fell in a river but a body has not yet been found.
Yesterday, a concerned resident had come forward saying they spotted a suspicious-looking vehicle, believed to be a Renault, outside a barn in St on the day Nicola went missing.
The witness contacted the police to report a suspicious "red van" parked in the village close to where Bulley went missing.
The 55-year-old witness, who had not been named, told the Times they saw the "tatty red van in Hall Lane outside a barn".
“I didn’t think anything at the time, but when I saw Nicola had gone missing, I called 101 and spoke to an operator.
“I contacted the police again on Friday and spoke to a police officer. It could have been a Renault van."
The St Michaels on Wyre resident said the vehicle was the "sort of van you can live in".
A second witness has also come forward saying they described the van as a high-sided Renault or Transit in a faded red.
A man in his 50s told The Sun: "It was a shabby-looking van, an older model, the kind you can live or work in.
"It was on a quiet lane near a barn, with a couple of houses dotted around.
"Obviously, I don't know whether this van is related to Nicola's disappearance. All I know is that something grabbed my attention. I felt compelled to tell the police about it."
It comes as detectives are looking into a mystery two-hour gap between the mum's disappearance and the first call to the police to report her missing.
Nicola was last seen at around 9.10a, and police were called until about 11am.
Lancashire Police have said they are working on the hypothesis that Nicola fell into the river, but no trace of the mum has been found after specialists have searched a mile-long stretch of the River Wyre.
Specialist Group International chief Peter Faulding said he is "100 per cent" sure Nicola is not in the stretch of river initially suspected, and his job is done.
Police have been forced to warn members of the public from taking law into their own hands when getting involved in the search, with a group last night understood to have been given a dispersal order.
Yesterday, the search moved to Morecambe Bay as two boats with specialist teams were seen in the sea.
There are at least three CCTV blind spots in the area where Nicola was last seen, raising the possibility that she could have left the area.
One spot is a path that is not covered by security cameras. It leads to Garstang Road which runs through the village.
It comes police are trying to get dashcam footage from about 700 vehicles that they have identified as passing along the main road through the village at the time Nicola vanished.
Another possible blindspot is a riverside path leading from the Wyreside Farm Caravan Park through to the A586.
A camera at a house is understood to have not been working at the time, but it still doesn't cover the exit.
Friends of Nicola have also claimed the CCTV covering one of the two exits from the river near the mobile home site Rowanwater, is not working.
Former Metropolitan Police Detective Chief Inspector Peter Kirkham has put forward seven key questions he believes need to be answered by the Lancashire Police enquiry team.
Anyone with information which could assist our investigation should call Lancashire Police on 101 quoting log 0565 of January 30th. For immediate sightings please call 999.
