Where there's smoke, there's the fire department

As I was getting ready to go to bed last night, I smelled smoke. It didn't smell like leaves, or wood. Rather, it smelled like paper was burning. Naturally concerned, I checked around the house, but didn't find anything smoldering. I had some windows open, so I checked to see if the smell was coming from outside. It didn't seem to be. Deciding the whole thing was no big deal I turned in. I hadn't been in bed a few minutes when I heard sirens. They grew louder, until it was clear they were coming into my neighborhood. Looking out my bedroom window, I could see blue and red flashing lights illuminating the backs of the houses behind mine. Dressing quickly, I headed for the front door. Outside, at least two fire engines and two ambulances were slowly making their way down my street, sirens now off, lights still going. They never stopped, just rolled slowly along until they came to the next intersection. One turned south, one turned north, and two kept going straight. Then, apparently, they went back to the fire station. I don't know if there was any connection between their arrival and the smoke I smelled, but it was an odd coincidence.