By Charlie De Mar

CHICAGO (CBS) — In Iowa this morning, the FBI has joined local law enforcement and the community in the search for Xavior Harrelson, an 11-year-old boy who disappeared last week.

CBS 2’s Charlie De Mar reports authorities are using dogs, drones, and dive teams as they desperately try to figure out what happened to Xavior.

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Investigators were at Xavior’s family home in Montezuma, Iowa, on Tuesday, hunting for information about his disappearance.

Authorities said Xavior was last seen on his bike near his home last Thursday morning, wearing a red shirt, blue pajama pants, and black shoes.

But neighbor Kelly Kautzer said she didn’t see him that morning, which was unusual.

“He was always outside, I’d say at least by 9 o’clock, riding his bike or just walking in the area. That’s about the time he’d start playing with my daughter,” she said.

Mitch Mortvedt, assistant director of the Iowa Division of Criminal Investigation, said authorities cannot rule in or rule out the possibility of foul play at this point.

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On at least one of the nights since Xavior has gone missing, temperatures in the area dipped to the 30s, and Mortvedt said as more time goes by, its more troubling that Xavior hasn’t been found.

“When it gets down into the 30s, of course, then you’re thinking hypothermia,” he said.

Over the weekend, hundreds of volunteers joined local police to search the area for Xavior.

People in Poweshiek County are still reeling from the disappearance and death of Mollie Tibbetts, a University of Iowa student who was found stabbed to death five weeks after she went missing in 2018. Last week, on the same day Xavior disappeared, a jury convicted farm worker Cristhian Bahena Rivera of kidnapping and killing Tibbetts.

“My biggest fear now is never knowing,” said Samantha Rix, whose son is close friends with Xavior. She is helping lead the effort to find him, and first reported his disappearance.

“I’m not stopping. I won’t stop looking for that little boy. I won’t stop putting his name out there, his face out there. I’m going to keep it fresh in everybody’s heads. I don’t care if it’s 10 years from now. I don’t care if it’s 50 years from now,” Rix said.

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Investigators said Xavior’s family is cooperating, but they did not want to talk at this time.

Charlie De Mar