Dale Wondergem Jr., 68, and Marcus Johnson, 14, were in the pit area when they were hit about 6 p.m. Saturday at the Marysville Raceway Park, about 40 miles north of Sacramento, according to the Yuba County Sheriff’s Department. Wondergem, of Grass Valley, was pronounced dead at the scene, and Marcus Johnson, of Santa Rosa, was pronounced dead shortly after arrival at a hospital, authorities said.

Marcus Johnson was identified by authorities as the cousin of 17-year-old driver Chase Johnson, who was not injured in the collision. The younger victim was not an official member of his cousin’s crew. Authorities are investigating why he was in the pit area, according to Undersheriff Jerry Read said.

The Marysville raceway was hosting the California Sprint Car Civil War Series on the opening day of its season. Wondergem owned one of the race cars at the track Saturday, but not the one involved in the crash, Read said.

The crash occurred when six or seven “winged sprint cars” were doing warm-up laps before the start of a scheduled race. Chase Johnson’s car left the track at an undetermined speed and hit Wondergem and Johnson before it tipped on its side, sheriff’s officials said.

The Yuba County Sheriff’s Department and California Highway Patrol are investigating the cause of the crash. Investigators will conduct autopsies on the victims on Monday and Tuesday.

No one else was injured in the crash, and spectators were never in jeopardy, authorities said.

Messages left for the Marysville Raceway’s spokesman and promoters were not immediately returned Sunday.

Chase Johnson of Penngrove is a senior at Petaluma High School north of San Francisco and is a fourth-generation race car driver, according to his website. He did not respond to an email seeking comment Sunday.

Johnson has been racing for three years at the Petaluma Speedway, where he’s won multiple races and was last year’s series champion. His father, grandfather and great-grandfather were also champion drivers in Petaluma, where the family owns a muffler shop, said Ron Lingron, the track announcer at Petaluma Speedway

“They’re the first family of the Petaluma Speedway,” Lingron said Sunday. “There’s not a better kid you’re going to find in the racing community than Chase Johnson. To have something like this put around his neck is a tragedy.”

Steven Blakesley, a race announcer who was watching from the stands, said he thought Chase Johnson’s car had a mechanical problem because he was driving about 90 mph and couldn’t make a turn or slow down just before the crash.

“People getting hurt in the pits is extremely, extremely rare,” Blakesley, who is the track announcer at Watsonville’s Ocean Speedway, said Sunday. “I’ve never seen anything like this, and I don’t know how you would even prevent it.”

The sprint car circuit is seen as a stepping stone to higher levels like NASCAR and many drivers start racing as young as 15, as Johnson did, Blakesley said. Others on the circuit, where small, high-powered cars race on short dirt ovals, were older drivers whose careers had peaked earlier.

Two-time NASCAR Nationwide Series champion Ricky Stenhouse Jr. began his career in sprint cars at age 15. He said current hotshot NASCAR racer Kyle Larson was racing sprint cars around California at 12 years old.

“People who can afford to go race somewhere are going to find somewhere to race,” Stenhouse said. “And the crews, the people in the pits? That’s almost always your friends and your family. I read somewhere somebody said those people shouldn’t have been in the pits. Well, this is how it’s done. This is the way of life.”

The race track fatalities come less than a month after a crash on the last lap of a race at Daytona International Speedway injured at least 30 fans Feb. 23. The victims were sprayed with large chunks of debris — including a tire — after a car careened into the fencing that is designed to protect the massive grandstands lining the track.

At another NASCAR race in 2009 at Talladega, the crowd was showered with debris and seven fans were injured when a car sailed upside-down into the front-stretch fence on a furious dash to the finish line, showering the stands with debris. Seven fans sustained minor injuries.

And in 2010 at a National Hot Rod Association event in Chandler, Ariz., a woman was killed by a tire that flew off a crashing dragster at Firebird International Raceway.