Clary Fray: The angels would never be in favor of killing millions of innocent Downworlders along with demons.

Malachi Dieudonné: When Raziel created the first Shadowhunter, there was no such thing as Downworlders. But over the centuries, disgusting half-breeds emerged. Warlocks, vampires, Seelies, werewolves. They banded together, grew more powerful. Finally they will be destroyed. And so will you.

From Shadowhunters – Season 2 Episode 20: ‘Beside Still Water’ (2×20)