The three Camp Lejeune Marines found dead in a car on Sunday 20 miles from the base died of carbon monoxide poisoning, autopsies found.

The Pender County Sheriff’s Department released the results of the men’s autopsies Wednesday afternoon. The autopsies, the Sheriff’s office said, were performed “by the North Carolina Office of Medical Examiner. All three deaths are consistent due to carbon monoxide poisoning.”

The Marine Corps identified the three men, all Lance Corporals, as Tanner J. Kaltenberg, 19, of Madison, Wisconsin, Merax C. Dockery, 23, of Pottawatomie, Oklahoma and Ivan R. Garcia, 23, of Naples, Florida.

Carbon monoxide is produced by combustion engines and, at high concentrations, stops the lungs from absorbing oxygen. Poisoning from the odorless, invisible gas kills at least 400 around the U.S. every year.

Officials did not say whether the men’s death is now considered accidental or intentional.

Reported missing by a parent

Sheriff’s deputies found the three Marines just after 9 a.m. on July 23 inside a car parked at a convenience store in Hampstead, North Carolina, a town about 20 miles south of Camp Lejeune. Officials said that Kaltenberg’s mother contacted police just after 8 a.m. to report her son missing. The Marine had been scheduled to be on a flight to Oklahoma the night before but had not arrived. Hampstead is about halfway between Lejeune and Wilmington International Airport.

Though they all wore the same rank, Garcia enlisted in the Marines in July 2019, Dockery in June 2020, and Kaltenberg in May 2021. All three Marines served as motor vehicle operators with Combat Logistics Battalion 2, Combat Logistics Regiment 2, 2nd Marine Logistics Group, Marine officials said.

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What is Carbon Monoxide Poisoning?

Carbon monoxide, or CO, is produced by the combustion of fuel, such as inside car engines, gas stoves, and portable electric generators. At least 400 people in the U.S. are killed every year by CO poisoning, according to the Centers for Disease Control, though some studies have put the number over 2,000. Most of those deaths are caused by portable electric generators, which can produce as much of the gas as hundreds of cars.

Prolonged exposure to CO can cause loss of consciousness, the CDC says, with headaches, dizziness, weakness, nausea, and confusion as early symptoms.

To avoid carbon monoxide poisoning, the CDC recommends:

  • Never use a gas range or oven to heat a home.
  • Never leave the motor running in a vehicle parked in an enclosed or partially enclosed space, such as a garage.
  • Never use a generator, pressure washer, or any gasoline-powered engine inside or within 20 feet of a window, door, or vent.
  • Maintain the batteries in a CO detector in your home.

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