(CNN) -- Skeletal remains found near an Arizona campground are believed to be those of a missing 2-year-old, the Yavapai County Sheriff's Office said Tuesday.
Sylar Newton was reported missing July 25 from the Beaver Creek Campgrounds in Rimrock. Authorities said last week that the boy was presumed dead as they announced the launch of a criminal investigation into his disappearance.
The remains were found Tuesday afternoon at the bottom of a wash less than two miles from the campground, the sheriff's office said. The office said the remains "likely came to rest in this area due to recent flash flooding."
"At this time, the remains are believed to be that of Sylar Newton, but final confirmation is still pending," the sheriff's office said.
Sylar was last seen shortly after midnight July 24, sleeping in a tent with his family at the campgrounds. About 1:45 a.m. July 25, the family noticed that he was missing from his sleeping bag.
"The sheriff's office believes Sylar did not wander from the campground and he is presumably dead," Yavapai County Sheriff Steve Waugh told a news conference last week. "The search effort is now in a recovery mode and the investigation has become criminal in nature."
Sylar was camping with his custodial mother, Christina Priem, and her children, when he disappeared. Priem has said she was in the process of adopting the boy from his biological mother.
Sheriff's spokesman Dwight D'Evelyn said last month that "there's no evidence" that the planned adoption played a role in his disappearance, "but until we've exhausted every lead, all possibilities are being investigated."
About 25 other people were at the campground the night of Sylar's disappearance -- all of whom have cooperated with investigators, according to the sheriff's office.