Searchers are using thermal imaging cameras and night vision goggles to look for a missing nine-year-old boy in Pennsylvania.

Hundreds of volunteers have been involved in the search for Logan Mitcheltree (search), who's autistic and unable to speak. He was last seen Saturday evening.

Authorities say the boy wasn't wearing a coat and the police chief in South Williamsport hopes he "found someplace warm." Temperatures have dropped to 15 degrees with winds making it feel close to zero.

The chief is asking searchers to focus on sheds or garages where someone might seek shelter from the cold.