Update:  The Highway Patrol has identified the victim as Andrew Williams III, 18, of St. Louis.  He apparently went under water while wading near the mouth of Perche Creek.

The body of a teenager was pulled from the Missouri River in southern Boone County Monday evening after authorities searched for him for several hours. Friends who were at the river with the teen reported him missing earlier in the afternoon.  The Missouri State Highway Patrol has not released the victim’s name.