The NTSB released a preliminary report on the collision between Air Canada Flight 8646 and a fire truck at LaGuardia Airport that killed both pilots.

Investigators said the truck had been cleared to cross the runway about 12 seconds before the plane touched down. A firefighter told investigators he then heard someone on the radio yell, “stop, stop, stop,” but was unsure who the warning was meant for.

More than 70 people were on board the flight, and about 40 people, including the two firefighters in the fire truck, were taken to hospitals.