The tour bus operator whose vehicle overturned on the 210 Freeway in Irwindale, injuring 52 people, has logged three moving violations this year, all of them out-of-state, federal records show.

The operator, Da Zhen Bus, was cited twice in February for exceeding the speed limit in Arizona -- once by 6 to 10 mph, and again by 11 to 14 mph. A bus also was cited in Nevada in May for driving too close to another vehicle, according to records with the Federal Motor Carrier Safety Administration.

Fifty-two passengers escaped with minor to moderate injuries Thursday when a Da Zhen tour bus overturned on the eastbound 210 Freeway just past the 605 Freeway interchange at 10 a.m., backing traffic up for miles as first responders descended on the scene.

The bus was headed to San Manuel Indian Bingo and Casino in Highland when, according to the California Highway Patrol, the driver tried to merge into a left lane and clipped the rear of a Hyundai Elantra with its left front end. After colliding with the Elantra, the bus driver swerved to the right, lost control and crashed.

According to the U.S. Department of Transportation, it was the first crash among Da Zhen’s fleet in the last two years.

Da Zhen's maintenance record, however, has more of a history. Over the course of two years, inspectors cited the company 25 times for a litany of safety violations, such as failing to secure a brake hose, having no or defective emergency exits and operating on a tire with tread less than 2/32 of an inch deep, records show.

The owner of Da Zhen Bus was unavailable for comment Friday.

Paul Hedlund, an attorney for a law firm that handles major transportation accidents, said that even though Da Zhen Bus’ safety record didn’t particularly stand out -- good or bad -- the number of moving violations was “higher than you want to see.”

He expected the Department of Transportation would look closely at what role the bus driver played in the crash, particularly given witness and CHP accounts of erratic swerving in the moments before the bus overturned.

“They’re going to be looking to see if there’s driving violations,” Hedlund said. “Any sort of erratic steering input in a bus is almost always catastrophic.”

ALSO:

Portion of 60 Freeway to be closed this weekend for repairs

Filner signs resignation letter ahead of council's settlement vote

Hannah Anderson says she's 'hanging in there' in first interview

jason.wells@latimes.com

Follow: @jasonbretwells / Facebook / Google+