Police, the fire service, fell rescue along with paramedics and the air ambulance are currently at the scene of a search of the River Wear, Paradise Park in the Witton Park area of Bishop Auckland.
Three people have been rescued from the river, but it is believed that a fourth is currently unaccounted for.
Officers are currently supporting the families of those involved.
River search ongoing at Witton Park, Bishop Auckland. Police, Fire, Ambulance and Fell Rescue all working together locate missing male.
— Durham Constabulary (@DurhamPolice) July 5, 2015