Cleo Smith's biological father has reportedly spent three hours talking to police after his four-year-old daughter went missing at a remote campsite.
Seven News reported that Daniel Staines was asked to give a statement at Mandurah Station, 1000km south of where Cleo vanished.
He reportedly did so willingly and appeared with his parents by his side. There is no suggestion he has anything to do with his daughter's disappearance.
It came as police released footage of the campsite Cleo disappeared from as a desperate search for the missing four-year-old enters its third day.
Cleo was last seen about 1.30am on Saturday at the Blowholes Campground in Macleod, about 50km north of Carnarvon in Western Australia's north.
Her parents woke up a few hours later at 6am and realised she was gone, and set about raising the alarm with other campers before contacting police.
The remote campsite, popular among Carnarvon families, is surrounded by sand dunes, shrub lands and rocky terrain, with a few surrounding beach shacks owned by locals.
Apart from the small cluster of shacks and caravans, the area is desolate, with a pristine beach the only thing disrupting the otherwise sparse landscape.
The grounds are named after nearby blowholes, which can be observed about one kilometre north of the campsite when waves smash against the cliffs and shoot through rock holes, sometimes up to 20 metres high.
Adjacent to the campsite is a white sandy beach and coral-filled lagoon, which is popular among families for snorkelling and picnics.
While picturesque, the area can also be deadly, with 'king waves' – powerful, unexpected waves up to 10 times bigger than the waves before them that come without warning, a frequent occurrence.
The Carnarvon Shire Council closed the Blowholes observation area in July this year due to dangerous king waves after a person was nearly swept into the ocean.
"There is a well-documented history of multiple fatalities and injuries on the Quobba coastline from king waves," the council's warning read.
"King waves inundate areas of coastline far above the normal expectations of most people. Extreme caution is advised visiting this coastline at present."
A Malaysian man was killed slightly north of the blowholes in 2013 after being swept off a rock by a freak wave while fishing with a friend.
The incident sparked calls for multilingual signs to be erected in the area to warn the public about the frequent occurrence of the brutal phenomenon.
While the swell in the area has been low over the past few days, 'very rough' waves are expected to hit heights of 4m by tomorrow night.
Police 'not ruling anything out'
WA Police Inspector John Munday revealed that in the search for Cleo, authorities were "throwing everything we can at this search in these initial stages".
Inspector Munday said on Monday extensive assets had been deployed in the search for Cleo, with authorities determined to not rule out any cause for her disappearance.
An Australian Maritime Safety Authority jet had been brought in, along with other patrols including drones, helicopters and SES crews.
Police were investigating the possibility that Cleo had been abducted, revealing that her red sleeping bag was also missing from the campsite.
"It's a very tough environment there, we feel desperately for the family in this very unusual situation where we don't know where Cleo is," Inspector Munday said.
"We have extensive assets there; police, local rangers, the SES, and community members.
We've brought in forensic examiners from our homicide and crime division as well, we're not ruling anything in or out."
He said on Sunday crews were "going as hard as we can, as long as we can, to try and find Cleo."
Police are also investigating the prospect that Cleo had wandered off and become lost.
So far, three nautical miles south of the camp has been covered in the marine search, as well as one nautical mile north, and one nautical mile out to sea.
Land searches had covered one kilometre north, one kilometre south, and 800 metres inland from the campsite.
Inspector Munday said he was confident rescue teams had covered the land area that Cleo could have realistically travelled on her own.
He remained hopeful the young girl would be found alive, noting the mild conditions were conducive for survival, given it hadn't been warmer than 24 degrees or colder than 15.
Cleo was last seen wearing a pink/purple one-piece sleepsuit with a blue and yellow pattern.