GILLETTE, Wyo. (AP) — Officials in Campbell County are trying to find out why some of the northeast Wyoming county's emergency warning sirens didn't go off when four tornadoes touched down last week near Gillette.

Seven homes were destroyed and 12 others damaged by the tornadoes last Friday. There were reports that two people received minor injuries.

Campbell County Emergency Management Coordinator David King told county commissioners that all the commands were coded and entered correctly and that the sirens should have worked.

King said the failure of the siren system demonstrates the need for never relying on one single warning system. He recommended people look into getting smartphone apps, adding that many people were successfully warned by those apps.

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