Wasn't it around 1990 or so that a guy - also in NYC - firebombed a "social club" and killed 87 people - all without the use of any firearm?
He poured gasoline inside the doorway, the only way in or out, and lit it. The entrance was at the base of a stairwell and there were fans (I think) upstairs for ventilation, so the fumes were sucked up into the room. A few, a very few, people near the door escaped by leaping through the flames. Almost all the deaths were caused by smoke inhalation.
IIRC, the guy is in for a nice loooooong stretch. IMNSHO he should've been publicly crucified, and I mean that literally. Sorry little SOB killed all those people because the "object of his affection" didn't return the feeling.