A beanie belonging to missing 11-year-old Luke Shambrook was found Monday afternoon west of the Devil’s Cove and Candlebark campsite, Victoria Police say.

A police image of the beanie.

Police say it is unclear when the beanie was dropped as the four-day search continues for the autistic boy, who was last seen by family on Friday near Lake Eildon, in Victoria’s north-east.

Rescue efforts resumed at first light on Monday, with fresh hope after a possible sighting.

• Search for Luke enters fourth day
• Family ‘glimpses’ autistic boy lost in Victoria
• Search for William Tyrell heads for swamp

A lone boy was spotted in the bush late on Sunday.

The Shamrock family with Luke, far left. Photo: AAP

On Monday Luke’s family released a statement through Victoria Police.

“We continue to express our thanks to all involved in searching for Luke,” the statement said.

“Everyone’s ongoing involvement and support is overwhelming and still greatly needed.”

A Victoria Police spokesperson said a family that was driving in the Devils River area on Sunday told police they saw someone matching Luke’s description.

“So, they have extended the search to cover that area,” the spokesperson said.

Campers are helping rescue teams involving the air wing, dog squad, local police and SES volunteers in the search of thick bushland.

The state’s SES service has asked the public not to head to the area to help with the search.

“While we understand that everyone is worried about Luke, we ask people not to head to the area to help out,” a Sunday night post on Facebook said.

“At this stage, more people will only complicate the scene.

“Help will be requested if needed.”