A lack of oxygen that incapacitated the pilot and three passengers is likely what caused a private jet to become unresponsive before flying over the nation’s capital and prompting the military to scramble fighter jets in 2023.

More details are emerging about four people killed when a private jet crashed in Virginia after causing a scare over Washington.

The plane that crashed was registered to Encore Motors of Melbourne Inc, which is based in Florida. John Rumpel, a pilot who runs the company said his family was returning to their home in East Hampton, on Long Island, after visiting his house in North Carolina.