Police activity has prompted the closure of a stretch of lanes of the northbound 5 Freeway in Anaheim near Disney Way until further notice, according to the California Highway Patrol.
Vehicles are being directed off at Lincoln Avenue. A SigAlert has been issued for the area.
According to CHP, authorities are dealing with a distressed individual on the freeway, which prompted the closure.
Drivers should expect major delays. Video of the scene shows a massive congestion of vehicles.
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The incident began at about 3 a.m. Wednesday. As the noon hour approached, efforts were continuing to get the person to safety.
Further details were not immediately available.