SAN FRANCISCO
06/21/2013 01:48 pm ET | Updated Jun 22, 2013

Frank Primus, Passenger, Saves Runaway Bus During Crash Through San Francisco Park (VIDEO)

When a San Francisco city bus accidentally careened through a public park on Thursday afternoon, it was only the quick thinking heroics of one passenger that stopped the massive vehicle from driving straight into four lanes of oncoming traffic.

At around 6:20 p.m., a 43-Masonic Muni bus carrying a dozen passenger collided with a black Volkswagen Jetta that was attempting to make an allegedly illegal turn in front of the bus. The bus's momentum was great enough to carry it, along with the car, off the road and into a public park--forcing nearby pedestrians to jump out of the way in order to avoid being run over.

"People were falling on the ground, glass was shattering, we were running into trees," passenger Dr. Frank Primus, who is in his residency to become a surgeon at University of California San Francisco, told KTVU.

To make matters worse, the park also serves as an exaggerated median--with four lanes of busy traffic on the other side.

"I realized were were heading toward Fell [Street] and we weren't stopping," said Primus. "The guy wasn't stopping the bus."

Jumping into action, Primus sprinted to the front of the bus and saw that the driver appeared to be in shock.

"His eyes were open and he was mumbling something, so I just put my foot on the brake and stopped...[the bus] before it went into Fell. At the time, you just do it, you don't think about it and I'm glad I did something."

Muni Spokesman Paul Rose told Bay City News that the bus driver was taken to San Francisco General Hospital.

However, largely as a result of Primus's actions, there were no injuries outside of the bus driver. The driver of the Jetta, who seems likely to be cited for a traffic violation, refused medical aid.

Correction: The article originally stated that Primus was in medical school instead of in his residency.

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