An Air Canada-operated aircraft collided with a fire truck on a runway at United States New York’s LaGuardia Airport on Sunday, killing the pilot and co-pilot and injuring two others.

Around 11:40 p.m., a Jazz Aviation flight operating on behalf of Air Canada struck a Port Authority Aircraft Rescue and Firefighting vehicle that was responding to a separate incident, according to the Port Authority of New York and New Jersey, according to CNN.

“Emergency response protocols were immediately activated,” the spokesperson said. “The airport is currently closed to facilitate the response and allow for a thorough investigation.”

According to the report, two people inside the fire truck were injured in the crash.

The truck had been preliminarily cleared and was responding to a nearby aircraft that had requested assistance after reporting an unknown odor in the cockpit, the official added.

The Port Authority has not released details on any injuries. Photos and videos from the scene showed the aircraft’s nose was heavily damaged.

Jazz confirmed the incident involving Air Canada Flight 8646 from Montreal in an early Monday statement.

The airline said the CRJ-900 aircraft was carrying 72 passengers and four crew members, based on a preliminary manifest.

The flight departed Montréal–Trudeau International Airport shortly after 10:30 p.m. ET and landed at LaGuardia about an hour later, according to flight tracking data from FlightRadar24.