"We will be continuing this investigation. It is not going to stop, and I am not going to cease in dedicating resources to locating Kyron," says Multnomah County Sheriff Dan Staton, who adds that the boy's family understands the change.
Although some local search and rescue crews will remain on call to follow up on any tips, most "will be going home," said sheriff's Capt. Monte Reiser.
Authorities said scaling back the search was a "natural progression" since searchers had already combed through the immediate area and "every location of interest."
Officials are now also offering a $25,000 reward for information that helps locate the 7-year-old. Kyron was last seen walking to his classroom after he attended a science fair at Skyline Elementary in Portland, Ore., with his stepmother.
The search for the boy intensified last week with hundreds of searchers scouring the grounds near his school and conducting door-to-door checks. The FBI, who interviewed 200 of Kyron's classmates and their parents, was also brought in to help with the investigation.
On Friday, Kyron's family spoke publicly for the first time, asking the public to "please help us bring Kyron home."