Three people have died after a news helicopter crashed near the scene of a fatal bus accident in suburban Los Angeles.

TV footage captured immediately after the crash shows flames shooting in the air and wreckage scattered between buildings in a parking lot in Chatsworth, about 40 kilometres from downtown Los Angeles

“The helicopter appeared to have landed on top of a shipping container and several vehicles parked in the area,” CBS reported.

“It happened near the scene of a metro bus crash that killed two people and injured six others… right now it’s unclear what caused the bus crash or the helicopter crash.”

Four patients were assessed at the scene, with three pronounced dead and one transported to a local hospital in an unknown condition, according ‌to Los Angeles Fire Department.

Several news helicopters ​were in the area reporting on the bus collision.

It was not immediately clear whether some of the people killed in the crash had been in the helicopter.

At least one person killed was outside in the parking lot, Captain Branden Silverman, a spokesperson for the LAFD, told a news conference.

“We’re trying to determine how many patients were inside the helicopter,” he said.

Silverman described the helicopter as “pretty well destroyed”.

Los Angeles Mayor Karen Bass said she ​was “devastated” ​by the loss of ​life in the helicopter crash ‌and the bus collision in Chatsworth, thanking emergency responders for their swift response.

–with AP / Reuters