All five people aboard a medical transport flight, including a patient, have been killed in a plane crash in a mountainous area in northern Nevada.

The Lyon County Sheriff's office said authorities began receiving calls about the crash near Stagecoach, Nevada, about 9.15pm on Friday and found the wreckage two hours later.

Stagecoach, a rural community home to about 2500 residents, is about 70 kilometres southeast of Reno.

Care Flight, which provides ambulance service by plane and helicopter, said the dead included the pilot, a flight nurse, a flight paramedic, a patient and a patient's family member.

Barry Duplantis, president and CEO of the company, on Saturday said relatives of all five victims had been notified, the Reno Gazette Journal reported.

"We send our deepest condolences to their families," Duplantis said.

The crash occurred amid a winter storm warning issued by the National Weather Service in Reno for large swaths of Nevada, including parts of Lyon County.

The weather service said it was expecting heavy snow, wind gusts of up to 105 kilometres an hour and periods of white-out conditions.

"It's a pretty mountainous region," Lyon County Sergeant Nathan Cooper said.

"Especially with the weather being the way it is right now, it's not very good."

The National Transportation Safety Board on Saturday said on Twitter that it is sending a seven-member team of investigators to the crash site. The NTSB is expected to release more information on Sunday at a news conference.

Care Flight identified the downed aircraft as a Pilatus PC-12 plane. Federal Aviation Administration records show the aircraft was manufactured in 2002.

The company said in a statement that it is halting flights to focus on helping responding agencies, team members and the families.