About 79 children in grades seven through 12 were gathering for evening worship Wednesday in the Family Life Center at Freedom Baptist Church in Laurel, Miss., when the floor gave way, NBC News reported.
The drop to the gymnasium floor was about 12 feet, said Jones County Sheriff Alex Hodge.
Twenty of the youths were hospitalized at South Central Regional Medical Center and Forrest General Hospital, though none had life-threatening injuries.
Authorities said they were investigating the cause of the collapse, which didn't appear to be weather-related.
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