(CNN) -- A second 2-year-old boy has gone missing in 10 days from Yavapai County, Arizona, authorities said Tuesday as they announced a major search effort under way for the toddler, identified as Emmett Trapp. Emmett's disappearance is believed to be unrelated to the case of Sylar Newton, another 2-year-old who was reported missing July 25 from a camping site in Rimrock, Yavapai County Sheriff's Office spokesman Dwight D'Evelyn said. Sylar's disappearance is now being investigated as a criminal case, authorities said Monday. Emmett was reported missing by his mother at 8 p.m. Monday, the sheriff's office said in a news release.
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Emmett Trapp was last seen Monday evening
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He is the second toddler to go missing in 10 days
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Officials do not think his case is related to Sylar Newton, missing since July 25
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