A teenager with non-verbal autism who has gone missing on a Victorian mountain could have walked into a house to find food and fall asleep, police have said.

300 people have joined the search for 14-year-old William Callaghan after he went missing from the south side of Mount Disappointment’s summit at around 2:20PM on Monday.

Temperatures in the area have dropped to 0C overnight and William is believed to have not been dressed for a cold morning.

Police have said the teenager is ‘very energetic’ and may have covered a large distancing.

They have also warned residents that he is very food-focused and could have walked into a home to eat before putting himself to sleep.

Residents in the vicinity of the mountain have been asked to check their bedrooms and outhouses and contact Triple Zero if they sight William.

There are no plans for the search to be stood down until the boy is found, police said.

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