Three people have been critically injured after a helicopter crash in Sacramento, according to the Californian city's fire department.

Images from the scene show a helicopter, which appears to provide air medical services, lying on its side on the eastbound lanes of Highway 50.

The crash was reported on Monday evening just after 7pm local time (3am UK time), according to local NBC TV affiliate KCRA, quoting traffic logs from the California Highway Patrol.

The news channel added that officials from the fire department said there was no patient on board, but there was a pilot, nurse, and paramedic.

One person was reportedly trapped under the wreckage of the aircraft.

"There has been a harrowing helicopter crash on 50 eastbound west of 59th St," Sacramento mayor Kevin McCarty said in a p

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