Former detective says police are lagging in search for missing mother Samantha Murphy

A former detective has accused Victoria Police of lagging in the Samantha Murphy investigation, as the search for the missing mother enters its seventh day.

Samantha Murphy was last seen leaving her home on Eureka Street in Ballarat East to go for a run in the Canadian State Forest about 7am last Sunday.

Local police, SES and community members were leading the searching for the mother of three until yesterday, when it was announced the Missing Persons Squad would take over.

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They were also helping in search efforts before being appointed as the lead investigators.

Former homicide detective Charlie Bezzina told Today that he was "surprised" the specialised crew wasn't called in sooner to help.

"I would have expected that the missing persons would have been on the ground on the following Monday after she went missing," he said.

"We have a mother of three here, very well respected in the community that's gone missing, inexplicably, so that should have, created a dual investigation."

Bezzina also mentioned that there are mine shafts scattered around the Canadian State Forest, where Murphy is believed to have gone missing, and said that locals had mentioned that to police.

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"I think the mines have to be now looked at to see whether she may have fallen into one of those, for all we know she may be injured in a mine shaft," Bezzina said.

"Have the police started looking at that? Have they approached professional, mine searchers to have a coordinated search on that?

"The fact is, if she is lying injured in a mine shaft, have they actually targeted that as mentioned by the locals?

"That's an avenue of inquiry that needs to be looked at and eliminated."

The detective also explained how investigators would use GPS tracking to help in the search effort.

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The mother's phone was last pinged at a telecommunications tower in the Buninyong area, about 11 kilometres south of her home.

"(It's) absolutely crucial from the very outset because obviously, battery life is an issue."

"They would be relying very, very heavily on the GPS coordinate through her smartwatch, and/or Apple Watch and also the phone.

"They are the two crucial elements that they'll be looking at."

Police have said there is nothing "sinister" about Murphy's disappearance.

Detective Acting Superintendent Mark Hatt told the media yesterday that the Missing Persons Squad would provide additional resources to aid in the investigation.