Chicago (CBS) — Authorities have released the name of the 12-year-old girl who died after a snow fort she and another girl built collapsed on top of them on Sunday.

Esther Jung, of Elk Grove Village, was playing outside in the snow with a 9-year-old girl Sunday afternoon in Arlington Heights, while their families were attending church services at Rothem Church, in the 100 block of East College Drive.

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Arlington Heights police and firefighters were called to the church around 2:40 p.m., after a makeshift snow fort the girls had built in the snowbanks collapsed on top of them.

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The girls were discovered under the snow after their families went looking for them when they hadn’t been seen for about an hour.

The girls were transported to Northwest Community Hospital, where Esther was pronounced dead at 4:30 p.m. An autopsy has been scheduled for Monday.

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The 9-year-old was treated for hypothermia and was being held for observation overnight. She is expected to be okay.