The FAA reportedly found that two air-traffic controllers left LaGuardia’s control tower about an hour before their shifts ended on the night of a fatal March 22 collision between an Air Canada aircraft and an airport fire truck. Their early departure allegedly left remaining staff without backup during unusually heavy traffic, thunderstorms and disruptions, raising further questions about staffing and safety oversight at the airport.

The collision killed two pilots and seriously injured six other people aboard the Air Canada plane, which carried 72 passengers and four crew. The fire truck had been authorised to inspect a United aircraft after an aborted take-off and was crossing the runway when the Air Canada jet landed at about 11.30pm; the runway warning system did not sound an alarm. The FAA is reportedly seeking to dismiss the two controllers, but the NTSB’s investigation is ongoing and has not determined whether tower staffing contributed to the crash.