The New York Times reports that on Sunday morning, hours before 493 Myrtle Avenue collapsed, neighbors saw jackhammer operators working at the scene. They are thought to have been trying to do something about the huge crack in the building that was cited in the DOB complaint filed in May and is thought to be the cause of the cave-in. WPIX says building inspectors were actually on the scene, investigating reports of falling bricks, when 493 collapsed. Residents said the building “constantly shook” in the months before it fell. The building next door, 491, has been deemed unfit for habitation and is being torn down. Other nearby buildings may be evacuated as well.