Authorities say an 18-year-old man has died after falling off a tube raft on a northern Colorado River.

The Fort Collins Coloradoan reports the teen fell into the Cache la Poudre River on Sunday. His name hasn't been released.

Bystanders pulled him to shore and attempted to revive him. He was later flown to a hospital.

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Authorities say a 16-year-old who was also rafting on the Poudre on Sunday was rescued about 100 yards (90 meters) upstream after his tube became stuck on a low dam.

His name hasn't been released.