Deputies in rural central Missouri are investigating the death of a four-year-old girl who died early Sunday morning, her father said, when she was “beaten, submerged in a pond, then left to freeze on the bank,” the Benton County Sheriff’s Office reports.

James Mast, 28, called 911 just before 1 a.m. — when temperatures in Cole Camp were well below freezing — and said that the girl’s mother, 28-year-old Mary S. Mast, and a two-year-old boy were also severely beaten.

Ethan J. Mast, 35 and Kourtney T. Aumen, 21, have been arrested “pending multiple felony charges,” the sheriff’s office said.

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Mary Mast and the toddler were taken to Bothwell Regional Hospital in Sedalia and are recovering from their injuries.

The sheriff’s office said that more arrests are possible and declined to provide further information.

Authorities did not say if or how James Mast and Ethan Mast are related and said about Aumen only that she lives in “a neighboring residence.” The pair were booked at 1:30 a.m. according to court records, which say they’re on a 24-hour hold pending charges.

This is a development story. More details will be added as they become available.

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[Featured image: Ethan Mast and Kourtney Aumen/Benton County Sheriff’s Office]