Two Sets of Remains Found in the Search for Missing Idaho Kids JJ Vallow and Tylee Ryan

Authorities have confirmed that two sets of remains have been found during a search for missing Idaho siblings Joshua “J.J.” Vallow and Tylee Ryan -- but they have not yet been positively identified.

Authorities executed a search warrant on the property of the children's stepfather, Chad Daybell, on Tuesday. It was the second time that authorities had investigated the property. The remains were found during the search.

"After proper family notification, we would like to confirm at this time that investigators have discovered two sets of unidentified human remains," the Rexburg Police Department said in a statement on Wednesday afternoon. "Autopsy results are pending."

Daybell is married to Lori Vallow, the Idaho woman who was arrested in February on charges stemming from the disappearance of the children. Authorities allege that she has failed to produce the children or to present any evidence that they are safe.

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Vallow has been charged with felony counts of desertion and nonsupport of dependent children, resisting or obstructing officers, criminal solicitation to commit a crime, contempt of court and willful disobedience of court process or order for failing to produce the children. She has pleaded not guilty and is being held on $1 million bond.

J.J., 7, was last seen on Sept. 23 at his school in Rexburg. Lori subsequently withdrew J.J. from the school, telling the principal she wanted to homeschool him.

The last image of Vallow's daughter, 17-year-old Tylee, dates to a Sept. 8 day trip Tylee made to Yellowstone National Park with her mom, brother and uncle.