PRESCOTT, Wis. (WCCO) — Authorities say the 5-year-old boy with autism who went missing in Wisconsin on Tuesday has been found safe, and is reportedly in good condition.

Scotty Meyer, according to an aunt, was badly dehydrated, sunburned, covered with mosquito bites and suffering from a severe diaper rash, but otherwise he was OK.

“We are grateful to Pierce County Law Enforcement, volunteers, friends and family for all their support and dedication to helping us find our son,” said the Meyer family in a statement early Wednesday evening.

Scotty was first reported missing midday Tuesday after he had apparently slipped out of the house while the family’s air conditioning was being repaired.

More than 500 volunteers spent Tuesday searching through grass and wooded areas for Scotty after the boy wandered out his family’s Oak Grove home around noon.

Rose Poss, Scotty’s aunt said she hardly slept Tuesday night. She described the experience as “surreal.”

“We all felt like it was a movie or something,” she said. “It didn’t seem like it could be happening.”

Hundreds of volunteers started gathering for day two of the search Wednesday morning at Prescott High School. Authorities sent home volunteers Tuesday night and spent the night themselves using thermal imaging equipment to try to find Scotty.

There was one false alarm during the search Tuesday as a volunteer saw something that they thought might have been Scotty, but it turned out not to be him.

But at 8:05 a.m. Wednesday, an untrained 8-year-old house dog found Scotty about a half-mile away from his home, along a bluff by the Mississippi River.

(credit: CBS)

Jason Moser is the owner of the dog, an 8-year-old Golden Retriever called Autumn. Moser said he was motivated by his own child.

“We have a four-and-a-half-year-old, and we can’t imagine losing him,” Moser said.

Moser said Scotty immediately grabbed his water bottle and started drinking as Moser yelled for help and called 911. The sheriff said the bluff had been repeatedly searched.

“We searched that area five different times with five different groups,” Sheriff Nancy Hove said. “We just kept hunting that area. He could have moved. He could have shifted.”

Moser said Scotty was found wearing only his pull up diaper.

Scotty is being treated at an area hospital where he’s in stable condition, according to Children’s Hospital spokesman Justin Theodotou. He has been reunited with his parents.

Poss, Scotty’s aunt, said she can’t wait to hug him. She also thanked the hundreds of volunteers who helped in the search, especially the Moser family.

“The outpouring of people was incredible,” she said. “And Jason and Melissa Moser and their dog Autumn, we love them. They are wonderful.”