The body of Patric McCarthy was found about 2 and 1/4 miles from where he was last seen playing Monday near the family condominium on the edge of the White Mountain National Forest. The area had been searched several times, said Col. Jeff Gray of the Fish and Game Department.
"Basically (the searchers) had to be right on top of him to locate him in the vegetation," Gray said.
Gray said Patric apparently died of exposure, and that the state medical examiner would determine when he died. He said there was no sign of foul play or of a fall.
An emotional Steve McCarthy, Patric's father, broke into tears at a Friday evening press conference as he read a prepared statement of thanks addressed to those who helped search for his son.
"Everything good in people was shown by the outpouring of support in the search effort," he said. "We thank you, we love you and always remember Patric."
At the news conference, Gray said the boy's body was found in a thickly forested area near a brook.
As many as 500 people at a time had searched night and day for the boy, using helicopters, dogs, night-vision equipment and even kayaks on a river that runs through the mountains.
"We thought we were going to find him, especially today," volunteer Tony Castagna said. "We were just kidding ourselves, I guess."
Gray said the boy's body was found by an advance rapid-response search-and-rescue team made up of New Hampshire Fish and Game Conservation Officers and volunteers from Androscoggin Valley Search and Rescue.
Patric vanished as his family was packing to head home to Bourne, Mass., a day after celebrating the boy's birthday. Playing about 300 yards from the condo, Patric challenged his stepbrothers to a race back to the condo but never arrived. Authorities believe he tried a shortcut and got lost.
As the days stretched on, officials became concerned about whether the boy could survive in the open. The area got a drenching rain Tuesday and strong winds Wednesday. Temperatures dipped into the 30s and 40s at night.
Police had also searched many of the roughly 500 condos in the area, looking in crawl spaces, under beds and in closets. New Hampshire first lady Denise Benson had joined the hundreds of volunteers Friday.
The boy's uncle said Patric was not prepared for such a situation.
"He's scared to death of the dark," said Wayne Rutledge.
"When you don't know where you are and it's dark and you start thinking of mountain lions and other wild animals, what must go through a 10-year-old's mind," he said. "Your mind is your worst enemy. It takes a lot of self control.
Patric's father, Steve, and stepmother, Margaret, had spent the agonizing hours at the condo. His mother, Dee Murray, followed the news from Bourne.
The McCarthys are well-known in Bourne - the Cape Cod, Mass., town where they live - as owners of the Gray Gables Country Market, where a "God Bless You, Patric" sign now hangs. Neighbors there held a prayer vigil Tuesday night.