A 30-year-old man died after he climbed into the engine of a plane at Salt Lake City International Airport on Jan 1, US authorities said.

CBS News reported on Jan 2, quoting airport officials, that Mr Kyler Efinger, a resident of Park City, Utah, had breached an emergency exit at the airport.

He then ran to a runway where de-icing operations were under way and “crawled into an aircraft engine”, officials added.

The police later said the aircraft’s engines were running, CBS News reported.

It is unclear why Mr Efinger, who the police said had a boarding pass to Denver, climbed into the engine of Delta Air Lines Flight 2348.

The airline said the flight, which was about to depart for San Francisco, returned to the gate, where all 95 passengers got off, CNN reported. The flight was cancelled.

Delta Air Lines said: “As nothing is more important than the safety and security of our customers and people, Delta is fully cooperating with all aviation authority and law enforcement investigations.”

The police were alerted to the incident at about 9.50pm local time on Jan 1 after a store manager at the airport reported a disturbance involving a passenger on the secured side of the terminal, the authorities said.

At 10.06pm, the authorities found Mr Efinger’s personal items, including clothing and shoes, on one of the runways.

Minutes later, dispatchers told the police that a man was at one of the airport’s de-icing pads and had entered the plane’s engine.

Air traffic controllers were told to notify the pilot to shut down the engines, CBS News reported.

Mr Efinger was found unconscious inside the engine, the police said.

Police officers and airport employees got him out, and first responders attempted emergency life-saving measures, but he did not survive.

Officers said the Federal Aviation Administration and National Transportation Safety Board are investigating the incident.

A Transportation Security Administration spokesperson said it is working with authorities on the investigation.