NEW YORK (AP) — All but four of the passengers injured in Sunday’s deadly collision between an Air Canada plane and a fire truck have been released from the hospital, the airline said Wednesday, as crews began moving the mangled aircraft off the runaway at New York’s LaGuardia Airport.

The crash, which remains under investigation, killed two pilots. Roughly 40 people were treated at area hospitals for a range of injuries, some serious. Further details on the four people who remained hospitalized were not immediately available.

The plane, which originated in Montreal, was carrying 76 people, including the crew, when it slammed into the fire truck that had driven out onto the runway. Seconds before the collision, an air traffic controller had cleared the truck to cross the runway.

Since Monday, much of the wreckage had remained on the tarmac, blocking access to one of two runways at one of the country’s busiest airports.

The jet’s tail end was lifted onto a large dolly, which was then towed via long tethers by two vehicles driving side by side. Earlier in the day, much of the wreckage of the nose, which was obliterated in the collision, was cut away by work crews. As it was towed, the middle of the plane was supported by its own landing gear, which appeared to be intact.

In a statement, Air Canada said the plane would be taken to a hangar. The airline said it would soon begin the process of reuniting people with baggage and personal belongings.

After the collision, many onboard managed to escape the damaged aircraft, including a flight attendant who survived after being thrown onto the tarmac while still strapped in her seat.

The two pilots have been identified as Mackenzie Gunther and Antoine Forest. At least one passenger, Clément Lelièvre, credited their “incredible reflexes” in saving his life and those of others, noting they braked extremely hard just as the plane touched down.

The two Port Authority Police Department firefighters in the truck survived.