Crews are searching for the body of a Utah man who jumped into the Yellowstone River and went over a 308-foot waterfall.

Witnesses said the man climbed over the railing of an observation platform near the Lower Falls along the river in Yellowstone park, according to National Park Service officials.

The man, 20, is presumed dead. Authorities are not releasing his name until his family is notified. Crews have been searching for the man by helicopter and on the ground.

Erin Alberty