Here is a photo of a building on the North side of East 6th St., near Avenue D. This building had a really bad fire but I don't if it was the cause of the abandonment or came later when it was vacant.
The fire obviously involved the entire building and started either on the second floor or the ground floor. The photo shows at the bottom- the second floor, of the 6 story building. Some of the terra-cotta work over the windows on the second and third floors got so hot the pieces cracked and fell along with a few bricks. The sheet metal cornice on the very top basically disintegrated and the roof as well as all the floors show obvious daylight through the floor joists visible in the windows.

Vertically through the left windows, some cracks and shifting can be seen, especially in the brickwork between the second and third floor!
This building was in imminent danger of collapse during the fire. Shortly after this photo was taken the building was demolished with a crane having a clam-shell bucket (not the steel ball) on February 9th, 1976.
This was not the typical demolition method in NYC but in a building like this they did use a crane and with the clam-shell claw bucket used that to "bite" off and crunch small pieces of the walls at a time from the top down rather than trying to knock the entire wall down in one chunk!
I did find and take home one of the pieces of terra-cotta from those second floor windows, it was a griffin profile, and another piece- the keystone was a shield, but both were cracked really badly and missing chunks.