All six people aboard a small jet died when the aircraft crashed and burned in a field near an airport near Los Angeles on Saturday, local and federal authorities said.

The aircraft, a Cessna C550 business jet, was traveling from Las Vegas and crashed near French Valley Airport in Riverside County, about 85 miles (137 km) south of Los Angeles, at around 4:15 a.m. the Federal Aviation Administration said in a statement.

The passengers and pilot who died were all adults, Elliott Simpson, an aviation investigator for the National Transportation Safety Board, said at a news briefing.

The privately-owned plane crashed 300 feet from the runway at the small airport, after attempting an instrument landing as a marine layer weather phenomenon settled on the area, Simpson said.

The conditions appeared to have met minimum standards for a landing at the airport, he said.

Just days earlier, on July 4, a small aircraft with four occupants crashed near the same airport, killing the adult pilot and injuring three juveniles, authorities said.

In Saturday's incident, fire engulfed all but the tail of the aircraft after it crashed, Simpson said.

Aerial video from local media showed burnt rubble in the shape of a small aircraft in a blackened part of a field across the road from the airfield.

Radar data from flight tracking website FlightAware shows just one business jet traveling from Las Vegas to French Valley at the time. That plane circled once near the field before descending.

The sheriff's office in Riverside County, where the French Valley Airport is located, said officials responding to the crash located an aircraft fully engulfed in flames in a field and that six occupants were pronounced deceased at the scene.

The National Transportation Safety Board will continue to investigate the crash, with more results expected within the next two weeks, Simpson said. He did not release the names of the deceased.