West Australian police hold grave fears for a missing four-year-old girl on the state’s northwest coast as detectives investigate the possibility she was abducted.

Cleo Smith was last seen by her parents about 1.30am on Saturday at the Blowholes campsite at Macleod, north of Carnarvon.

The girl was wearing a pink one-piece sleepsuit with a blue and yellow pattern. She was in a red and black sleeping bag which has since been reported missing.

Homicide and major crime forensic investigators are assisting local authorities as the search for Cleo enters its third day.

Police have spoken to other family members and are searching a number of shacks located along the coastline at the campsite.

“We are continuing to throw everything we have at this and we will continue until we can provide some answers as to what has happened to Cleo,” Inspector Jon Munday told reporters on Monday.

“Certainly we are not ruling (abduction) out. We are not going to get blinkered or assume that something has happened. Everything is on the table until we can rule it out.”

A police helicopter and drones have also been deployed as part of an aerial search.

Inspector Munday would not comment on reports a car had been heard speeding from the campsite in the early hours of the morning.

He said the conditions near the tourist hotspot were difficult.

“Every hour that goes by with a four-year-old out in this environment, there’s obviously limited water supply, it is warm, very limited shelter. It is very, very concerning,” he said.

“That’s why we do hold grave fears for Cleo at this time.”

On Sunday, the girl’s worried mother, Ellie Smith, took to social media also pleading for help.

“It’s been over 24 hours since I last seen the sparkle in my little girl’s eyes! Please help me find her,” she posted.

Earlier, Ms Smith posted that she had woken at 6am on Saturday to find her daughter wasn’t in their shared tent.

She described Cleo’s disappearance as “very, very unusual”.

Police are “fairly confident” they had been able to get the identities of all those who were at the campsite, as well as gathering intelligence from dashcams and CCTV cameras in the vicinity.

Deputy Premier Roger Cook said Cleo’s family was going through “immeasurable pain”.

“All Western Australians’ hearts go out to them,” he said.

AAP

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