CORONA, Calif. -- Two private planes flying about a mile from an airport collided Sunday, killing at least four people and raining debris down on car dealerships below, authorities said.

The small Cessnas collided at 3:35 p.m. near the small Corona Municipal airport and a freeway in Riverside County, about 45 miles southeast of Los Angeles, FAA spokesman Allen Kenitzer said.

Three of the dead were from the planes and the fourth was in a car hit by debris on the ground, Kenitzer said.

The Corona airport does not have a staffed control tower, he said.

Debris fell on car dealerships, and TV pictures showed the smashed fuselage of one of the planes landed atop a parked car.

"The smaller aircraft ... just disintegrated into pieces, maybe 50 pieces coming down," eyewitness Jeff Hardin told KABC-TV.

Eyewitness Hector Hernandez said he saw bodies falling from the sky.

"One of them crashed into the top of a Ford Mustang, and another one fell not too far behind that one on the parking lot," Hernandez told KCBS-TV.

Police were going through the dealerships to see if anyone was injured, Corona Police Sgt. Jerry Pawluczenko said.