Something weird and spooky...

just happened a few minutes ago. I was working in my office with a door open and both of my cats were sitting outside on the second-floor balcony when these loud, awful hooting noises started in the backyard. My poor kitties ran into the house, obvioulsy terrified, and hid under my desk. After a moment of confusion, I realized that only owls would make such a sound! Because I live in a rather busy, although residential area, I haven't heard them before; however, there are lots of old houses around -- it's a historic district, after all. Something must have spooked them and they were raising an alarm. But in my backyard??? Go away!!! They were screeching for less than a minute but I was sure glad they left -- can't stand owls!