Five people were left injured after a dump truck caused a series of crashes in San Gabriel, California on Wednesday.

Filmed by two following motorists, the massive truck can be seen veering across the median, crossing into oncoming traffic and rear-ending a white sedan, completely crumpling its rear end.

The carnage then continues as the driver approaches an intersection where he rams into a line of four cars waiting at a red traffic light. A white Volvo XC90 takes the brunt of the impact and is pushed forwards into a Toyota Highlander which then hits a silver sedan.

San Gabriel police Lt. Fabian Valdez told local media Pasadena Star-News that the driver of the dump truck was found semi-conscious after the crash and may have suffered a medical episode when behind the wheel.

In total, the truck caused three separate crashes and struck eight vehicles.

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