Two Delta Airlines planes collided while taxiing at New York’s LaGuardia Airport, tearing the wing off one of the aircraft and leaving at least one person injured, authorities confirmed Wednesday.

The incident occurred on the tarmac at one of the nation’s busiest airports, sparking immediate questions about how such a mishap could occur under strict ground-control procedures. Passengers were safely evacuated, though one individual was treated for injuries.

Investigators are now working to determine the cause of the collision. Both planes sustained significant damage, leading to flight delays and diversions at LaGuardia.

The Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) have launched an inquiry into the incident.