Three killed in news helicopter crash in Los Angeles

Three people were killed when a US news media helicopter covering a fatal bus crash came down in a Los Angeles neighbourhood.

There was no immediate confirmation of the identity of those on board the helicopter, but police confirmed it was a media helicopter and the local NBC4 affiliate reported live that it was unable to make contact with its crew.

Aerial footage showed a large fire that appeared to involve shipping containers and cars, and the wreckage of a helicopter, whose mangled tail and rotors could be seen in the flames.

Media in the city were covering a collision between a bus and an SUV in the Chatsworth area in which three people were killed and many others injured.

Reporters who were at the scene of the bus crash said there was a loud bang, with some saying they saw a helicopter come down around a block away, sending plumes of smoke into the air.

During live coverage on NBC4, news anchor Colleen Williams confirmed it was the local news station's helicopter that crashed.

"We knew it was a news chopper. We knew we'd lost contact with our people out there, and we've just received confirmation," Ms Williams said.

Dozens of firefighters were sent to the scene, the Los Angeles Fire Department said.

"Four patients have been assessed. Three patients have been determined deceased on scene.

One patient has been transported to a local hospital in unknown condition," a statement said.

One of the dead appeared to be a person who was a pedestrian on the ground when the crash happened.

Los Angeles is a competitive and crowded media market, where TV stations compete aggressively for stories.

Many of them routinely make use of aerial coverage, sending helicopters into the city's already busy skies to cover everything from fires to car chases.

There are usually two people on board a news media helicopter - the pilot and the reporter-camera operator who frequently reports live from the sky.