The other day I was in a cab on my way to work when I discovered that the traffic on Dong-bu Ichon-dong was being stopped by police officers. Beyond the officers I could see that there were no vehicles on the road at all. I paid my cabbie and started to walk, which is when I finally figured out what was going on.
It was a test of the "North Korea is attacking!" sirens. I've heard them only once before and have never been outside to see it in action. All the cars pull over and stop. The street looks a bit frozen, with only the odd pedestrian walking around. I've never seen a Korean street so empty during the day - except when I was in Kaesong, North Korea.
Wish I had had my camera.