What is the most terryifying siren noise?

There's an emergency at the Facility down the road, and everyone in a six-mile radius is very likely fucked.

What is the sound that announces your fate?

• oooooOOOOOOOIPP, oooooOOOOOOOOIPP
• WAAAARK ..... WAAAARK ..... WAAAARK
• dyOOT! ... dyOOT! ... dyOOT!
• Something else? (please spell)