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 LA.

“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… right now it’s unclear what caused the bus crash or the helicopter crash.”

Three people were pronounced dead at the scene of the helicopter accident, with two others transported to a local hospital in an unknown condition, according ‌to the Los Angeles Fire Department.

Several news choppers had been in the area reporting on the earlier collision involving a bus and an SUV, which the LA Times reported also killed three people and left around six others injured.

TV network NBC4 confirmed that it owned the helicopter which crashed. News anchor Colleen Williams said staff at the station had been ready to go to air with the bus accident coverage when they saw a large plume of smoke and realised something else had happened.

“Just a couple blocks away, our helicopter went down – it crashed… It’s just so difficult to comprehend and to wrap your brain around,” she told viewers.

The deadly helicopter crash sparked a fire. Photo: AP

The Fire Department said two of those who died were on board the helicopter, while the third had been on the ground in the parking lot.

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.

LA County Supervisor Lindsay Horvath also said it had been a “traumatic day”, acknowledging that many people were affected by the two accidents.

“The riders who were on that bus, the Metro operator, and our bus operators across our system who mourn. Members of our local news community who came here to do their jobs and experienced a profound tragedy of their own.

“This has been a deeply traumatic day for far too many people.”

–with AP / Reuters