MARYSVILLE, CA (BCN) -The Yuba County Sheriff's Office is investigating why a racecar crashed and killed two people at the Marysville Raceway Park Saturday evening.

Marcus Johnson, 14, and 68-year-old Dale Richard Wondergem Jr. of Grass Valley died after a sprint racecar driven by Johnson's 17-year-old cousin, Chase Johnson of Penngrove, left the track and crashed in the pit area of the raceway in Marysville.

Wondergem died at the scene and Marcus Johnson died soon after he his arrived at Rideout Hospital in Marysville.

Yuba County Undersheriff Jerry Read said the investigation will include the possibility the steering wheel in Chad Johnson's car became disconnected, and that the car was traveling around 90 mph when it entered the pit area around 6 p.m.

"We have the car and we'll examine it. No one has reported seeing the disconnected steering wheel in his (Chase Johnson's) hands," Read said this afternoon.

Read also said, "We don't know how fast the car was going."

Wondergem owned one of the racecars at the track but not the one Chase Johnson was driving, Read said.

Chase Johnson was not injured in the crash that happened as the drivers of six or seven winged sprint cars were completing their "hot", or warm-up laps before the race.

Johnson's car tipped onto its side and stopped after it hit Marcus Johnson and Wondergem who were standing near each other, Read said.

It was reported that Marcus Johnson was not an official member of Chase Johnson's pit crew, and his presence in the pit area is still being investigated, Read said.

The racetrack was hosting its Battle of Marysville for the sprint cars Saturday. The race is part of the California Sprint Car Civil War Series.