BAUDETTE, Minn. (WCCO/AP) — Five men remain hospitalized after they were injured in an explosion in an ice fishing camper in northern Minnesota.

According to Lake of the Woods County Sheriff Gary Fish, the propane furnace exploded and blew out the windows early Sunday on the shore of Lake of the Woods at Zippel Bay.

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As of Tuesday morning, Rod Bolstad of Hillsboro, his sons Jacob and Joel Bolstad as well as Al Stokke and Willy Huotari were all still being hospitalized.

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Huotari and Jacob Bolstad were listed in critical condition, Rod Bolstad was in serious condition and Stokke and Joel Bolstad were listed in fair condition. The conditions of Rod Bolstad and Joel Bolstad were upgrades from what was reported on Monday.

While the cause is still under investigation, authorities say they are confident the explosion was accidental.

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