The crash happened about 1:30 p.m. at the Wells Cargo Self Storage on Camarillo Center Drive, which is just behind the Camarillo Premium Outlets and near the Camarillo Airport.
There were no reports of fatalities. All passengers were able to walk away from the crash just before the plane went up in flames.
"They were pretty bloody in the face but they were all walking," said witness Brett Hanley. "They jumped in my arms and I pulled them away from the wreck. Not too long after that the thing exploded."
All were taken to a local hospital, three with minor injuries and one woman with serious to moderate injuries.
"We know that the aircraft was coming from the Chino Airport and was en route and attempted to land at the Camarillo Airport," said Dan Horton of the Ventura County Fire Department. "They actually got within a half mile of the runway."
Witnesses said they knew the Beechcraft Bonanza was in serious trouble when they saw it in the air.
"It was coughing ? and the engine was running really rough," Hanley said. "It stalled and crashed nose down."
Authorities said nine storage units were destroyed.
The National Transportation Safety Board is investigating to determine what caused the crash.