I would more say it would be like Bhopal India and the Union Carbide failure it would most definitely be a nightmare.
Ammonia is some nasty stuff in mass quantities.
yes. Soft-flowing but deadly regional gas in the interior of buildings (no escape!) and exterior in the streets and sidewalks until vented and diluted by the winds - killing like Bhopal, not blast, flames, and fire damage like Hiroshima.
On the other hand, the Muslims may then consider that an advantage. They kill the tens of thousands near the ammonia tanks, but those deaths leave the houses and shops and all the clothes and interiors and all of the furnishings and cars and trucks and households clean and sterile and ready for use by the next bunch of Muslims to live in.
/sarchasm