Two people were killed from each plane, and a fifth was killed inside a Chevy dealership hit by wreckage, said Wayne Pollack of the National Transportation Safety Board.
"There were bodies falling out of the sky," eyewitness Hector Hernandez told KCBS-TV. "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."
Federal investigators had yet to cut all the way through the wreckage of one of the planes, and were unsure about the number of passengers.
"Until we open that aircraft up we cannot be certain how many people were on board," Pollack said.
The smashed fuselage of one of the planes landed atop a parked car. A wing from one of the planes sat in a parking lot. The debris was contained mostly within a 300-yard radius, said Pollack, although some pieces were found as far as 1,000 yards away.
"The smaller aircraft ... just disintegrated into pieces, maybe fifty pieces coming down," eyewitness Jeff Hardin told KABC-TV.
"The other aircraft pretty much stayed intact and started spiraling down and came down right behind the Nissan dealer."
One of the planes, a Cessna 172, is registered to William A.
Reinke of La Habra, Calif, according to aircraft databases. Reached at his home Sunday night, Reinke declined to say who was flying his plane or who might have been on board.
"I only know what happened off the television," he said.
Pollack said investigators had not yet obtained a flight plan.
The other plane, a smaller Cessna 150, is registered to Air Corona Inc., based in Dover, Del. Many plane owners register their aircraft in Delaware even if they are not based there because of the state's low taxes.
Federal Aviation Administration spokesman Allen Kenitzer did not immediately know where either plane was headed or whether there were any distress calls. The Corona airport does not have a staffed control tower, he said.
Before Sunday, there had been five fatal plane crashes in Corona in the past decade, killing 10 people, according to an NTSB database.
