5:50 p.m. Update: Officials say the crash was caused by a white van that failed to slow down to traffic, causing a chain reaction with four vehicles in front of it.

Officers said the person that died was an adult male in the fourth car in the crash. All the vehicles involved in the crash had solo occupants, CHP said.

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There were other injuries, but it is unknown at this time if all of the injured people were transported to the hospital.

CHP is investigating the crash.

4:50 p.m. Update: CHP Officers said the crash involved five vehicles and has closed down Highway 12 at Beck for approximately two hours.

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FAIRFIELD (CBS13) — Fairfield firefighters responded to a mass casualty incident on Highway 12 and Beck around 3:40 p.m. Wednesday.

California Highway Patrol Solano confirmed that one person has died in the crash and multiple vehicles are involved.

Drivers are being asked to avoid the area for the time being.

Traffic is being diverted off at Chadbourne Rd. Motorists are advised to expect delays and to use alternate routes to avoid the area.

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This is a developing story.