By Laura Haefeli

WALNUT GROVE (CBS13) – An Oakland man who crashed into the Sacramento River was rescued by a good Samaritan after pleading for help while standing atop his sinking car near Walnut Grove, the California Highway Patrol said on Thursday.

The driver, 67, reportedly suffered a medical emergency while behind the wheel on Twin Cities Road, which caused him to accelerate and continue through the T-intersection at River Road, authorities said. At around 10 a.m., the driver went off the roadway and into the river.

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The CHP said the man did not know how to swim but was able to get on top of the vehicle to call to witnesses on the shore nearby.

Chris Arias, 39, of Antioch, was on the bank of the river when he heard the man’s calls for help.

“He launched into the water like Mission Impossible,” said Arias, who the California Highway Patrol is touting as a hero.

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Arias jumped into the water and had the man hold onto his back while he swam them both to safety.

“The water’s freezing the currents really hard, so I just decided to jump in,” Arias said. “He was able to crawl on the hood a little bit to get out of the car. It started to sink pretty quick.”

The CHP said the driver was not injured in the crash, but details regarding the medical emergency were not released and he was hospitalized as a precaution. The man said he would have died if it wasn’t for Arias, according to the CHP.

His identity was not released.

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“We barely made it. He was pretty close to drowning,” Arias said. “Looking back, the little delays I had in my day, it all makes sense. I stopped at the store on a whim. If I had not done that I would have just drove right past it.”