Video posted on social media showed the plane engulfed in flames and plumes of black smoke billowing into the sky. The two people on board, a man, and woman in their 50's and 60's were hospitalized.
Orange County Fire Captain Larry Kurtz said the Cessna 310 crashed at 9:30 a.m.
California Highway Patrol said that the plane clipped the vehicle of an off-duty fire captain as it was coming down, though the captain was not injured, KCBS reported.
After an air traffic controller tells the pilot a gear of the plane appears to be up, the pilot says he's trying to gain altitude. The driver in that clipped auto told ABC7 that the plane hit the rear end of his truck, which then went out of control.
The crash involved a Cessna 310 airplane that landed and burst into flames on the 405 Freeway in the Irvine area, authorities said.
- Rafi Mamalian (@rafimama) June 30, 2017Just saw a plane just crash land on the 405 freeway right in front of me! One Twitter user called the accident the "scariest thing I've ever seen".
John Wayne Airport is closed to arrivals.
A witness told KABC-TV the plane first hit the northbound side of the highway, then "bounced" across the median to the southbound side.
He said the crash happened under "unknown circumstances".