A photographer on Friday caught some amazing video of a crash on Interstate 805 at University Avenue.
Officers said the crash occurred after a driver clipped a California Department of Transportation sign and it flew onto the highway.
Several motorists then hit the debris and traffic slowed behind them, including a semi-truck.
However, the truck didn't have enough clearance behind one of the vehicles and as it swerved to avoid a collision, the truck's trailer slammed into the back of a car, sending a flash of sparks into the air.
At least two cars were impacted by the semi.
The cars that were struck spun in different directions.
The truck's trailer swung wildly after the impact.
Debris from the crash littered the highway.
Fire crews said one person was taken to an area hospital after being hit by the semi
The crash snarled traffic on I-805 northbound for more than two hours. Click to read more .