NEW YORK - A new report by the FDNY is revealing new causes in a movie set fire that happened in Harlem last year.

City firefighter Michael Davidson died while battling the flames.

According to the report, Davidson died after collapsing from inhaling high levels of noxious gases in the building located at 773 St. Nicholas Avenue.

The report says the movie set was built with highly flammable materials that produced toxic smoke.

There were false plywood walls covered in polyurethane foam.

And the overall cluttered space created complications for firefighters.

All were factors that led to Davidson’s death. 

"It’s not surprising to me. I know that walking through here there was always a bunch of wires and stuff all over and i know the building was really old and it sort of seem like there wasn't a lot of preparation for that, and all of a sudden there was a movie set in the building," said one Harlem resident.

In addition to the flammable materials, the report found the movie set walls concealed the fire. 

The sprinkler system did not go off.

The cluttered conditions also caused confusion as to the source of the fire.

Davidson, 37, was a 15-year veteran of the city fire department. He was assigned to Engine Company 69.

Friends and neighbors of firefighter killed in Harlem remember his willingness to help others