CALABASAS (CBS/AP) —Officials said two small planes collided in mid-air Monday afternoon over Ventura County, killing one person and injuring three others.

Federal Aviation Administration spokesman Allen Kenitzer said preliminary radar records showed the two Cessna 172s crossed paths above 3,000 feet just after 2 p.m.

One of the aircraft, which had just departed from Santa Monica for an engine test flight, crashed into mountainous terrain along Las Virgenes Road and Mulholland Highway in Calabasas.

Firefighters, who were initially sent to the area to battle a brush fire, first discovered the burning remains of the plane.

One person, believed to be the pilot, was later confirmed dead.

“They have found remains of one individual. The crash site, as you might imagine, is hot,” said Los Angeles County Sheriff’s Department spokesman Steve Whitmore.

The other plane made a hard emergency landing at Westlake Golf Course at 4800 Lakeview Canyon Road.

Three people, including the pilot, were on-board the Cessna, which was registered to American Flyers—a flight school out of Santa Monica.

All three were transported to a hospital with non-life-threatening injuries.

A witness said the pilot initially told him a bird struck the plane.

“They said the reason for the crash was because (the plane) got hit by a bird,” said Ben Cochran.

The National Transportation Safety Board planned a news conference for 6 a.m. Tuesday.

The investigation is ongoing.

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