One person was hospitalized with serious injuries after being pulled from the Elkhorn River Saturday afternoon.
A water rescue call went out around 2 p.m.
Emergency response crews tracked the parties involved to a stretch of the river between West Center Road and Q Street.
Authorities on scene said two parties were initially stranded in the water and needed help, then a third person went under the water.
Civilians initiated CPR on one party before medics arrive. That person was taken to the hospital in serious condition.