SONOMA COUNTY (CBS SF) — Four people including an 18-month-old child were injured Friday morning in a horrific chain reaction crash that included a Sonoma County transit bus.

CHP Officer Matt Pinheiro said the crash on River Road began when a vehicle slammed into the rear of a car making a left-hand turn into a driveway.

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The vehicle then pivoted into the westbound lane and collided head-on into a Sonoma County transit bus which traveled a short distance before toppling on its side in a ditch.

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A passerby, Pinheiro said, rushed to the crumpled vehicle and pulled the injured 18-month-old from a car seat.

“It could have been so much worse had the child not been properly placed in the car seat,” Pinheiro said.

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The bus was also empty of passengers. The drivers of the bus, vehicles and the child were rushed to the hospital with moderate injuries.

Source: sanfrancisco.cbslocal.com.