A pilot has been indicted for allegedly threatening to shoot the plane’s captain if the captain diverted the flight because of a passenger who needed medical attention.

A grand jury in Utah issued the indictment against Jonathan J. Dunn on Oct. 18 over an incident that happened in August 2022, charging him with interference with a flight crew, according to federal court records.

The Transportation Department’s inspector general’s office said in an email sent Tuesday that Dunn was the first officer, or co-pilot, on the flight and was authorized to carry a gun under a program run by the Transportation Security Administration.

“After a disagreement about a potential flight diversion due to a passenger medical event, Dunn told the Captain they would be shot multiple times if the Captain diverted the flight,” the inspector general’s office said.

The inspector general described Dunn as a California pilot. It did not identify the airline on which the incident occurred, saying only that it was a commercial airline flight. The office did not give the flight’s intended route, or whether it was diverted.

The inspector general said it was working with the FBI and the Federal Aviation Administration on the investigation.

The two-page indictment in federal district court in Utah says only that Dunn “did use a dangerous weapon in assaulting and intimidating the crew member.” It did not indicate the airline either, and the U.S. Attorney’s Office in Salt Lake City declined to comment beyond the information in the indictment.

Interference with a flight crew is a felony punishable by up to 20 years in prison.

An arraignment is scheduled for Nov. 16.

The pilot’s indictment came just a few days before an off-duty Alaska Airlines pilot riding in the cockpit jump seat tried to shut down the engines of a Horizon Air jet in midflight. He was subdued by the captain and co-pilot and arrested after the plane diverted to Portland, Oregon.

Joseph David Emerson of Pleasant Hill, California, told police he was suffering from depression and had taken psychedelic mushrooms 48 hours before the flight. He pleaded not guilty in state court in Portland to charges of attempted murder.

That incident revived debate about how pilots are screened for mental health — largely by trusting that they will volunteer information that could raise safety concerns. Pilots are required during regular medical exams to disclose depression, anxiety, drug or alcohol dependence, and medications they take.