"We believe Jayme was in the home at the time of the homicides and we believe she's in danger", Barron County Sheriff Chris Fitzgerald, who is leading the search, told a news conference.
Jayme disappeared this week from her home in Barron, Wisconsin, where her parents were discovered dead in the early hours of Monday morning, authorities said.
There is no history of run-ins with law enforcement at the home, including no custody disputes, he previously said. Jayme wrote that she would "feed the hungry and give the rest to the poor".
He said that the autopsies of James and Denise Closs were completed. They did say the only discernable sounds were background noise. But no one spoke directly to the dispatcher, Fitzgerald said.
Federal Bureau of Investigation officials in Milwaukee said on social media at the time that it appeared that Jayme may have been "taken" from her home, "likely with a gun".
"Often, someone in the community will have knowledge of a crime and may not realize it", he said. No vehicles were found in the immediate area, the sheriff said. Meanwhile, authorities say they've gotten more than 200 tips following an Amber Alert that was issued Monday afternoon. She was still missing last night, four days after the 911 call.
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Its pupils are mostly teenagers. "A lot of dead bodies, a lot of children's dead bodies". "This is not a terrorist act". State-run news agency TASS reported that most of the victims were students, quoting local ombudswoman Lyudmila Lubina.
"This is a hard time for our entire team and we are mourning this loss and are still processing this awful tragedy".
Authorities did not release additional details about what the search would involve.
Shortly before 2 p.m., volunteers gathered and started searching in front of the Closs home off Highway 8 after splitting into two groups - everyday citizens who looked for clues while walking west, and members of law enforcement doing the same heading east from the house. They also know whose phone dialed 911, but they have yet to name the device's owner.
"It was just, "bang" and 'bang, '" Smrekar said.
Anyone with information regarding Closs' whereabouts or who may have had contact with her is asked to contact the Wisconsin Department of Justice Child Abduction Response Team tipline at 1-855-744-3879.
Office of School Safety (OSS) is working with Wausau Police Department and the Wisconsin Safe and Healthy Schools Center to deploy trained therapists, school resources officers, and comfort dogs to Barron School District, in the aftermath of the disappearance of 13 year-old Jayme Closs.