HOUSTON, Minn. (AP) — Authorities in southeastern Minnesota say a camper poured a flammable liquid on a campfire, sparking an explosion that injured four children.

The Houston County sheriff’s department received a 911 call Friday evening from the Money Creek Haven Campground in Houston. The caller reported an explosion.

A boy and a 4-year-old girl were airlifted to hospitals in St. Paul and La Crosse, Wis. Two other kids were taken by ambulance to a La Crosse hospital. The extent of their injuries hasn’t been released.

Deputies say an adult poured flammable liquid on a smoldering fire. The liquid ignited, causing the container to catch on fire as well.

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