Let me preface this by saying I live on the 3rd floor of a 3-story suburban apartment building, and it's roughly 30 feet to the ground from the roof. Each floor has a balcony, and other than that, there's not much on the outside of the building. I also have a high living room ceiling with a skylight (which has a curtain over it).
At about midnight Sunday night, I heard what sounded like slow footsteps across the roof, as if someone was trying to be stealthy.
This was not the right time of day for roof maintenance.
Then, I heard fussing with the skylight, prying and poking. I called security and they said they'd be right over. I'm looking around for a blunt instrument at this point.
I leaned out on the landing and said something I won't repeat, and the noise stopped.
As the patrol SUV rolled slowly through the parking lot inspecting the building, I heard a racket outside on the balcony, and then silence.
The patrol guy had stopped and was just standing casually outside his vehicle. Hmmm. I guess nobody threatening-looking ran by. I stepped outside with a flashlight, shining it into the parking lot, and saw... two plump raccoons waddling away across the parking lot into the night.
Did I mention I live on the 3rd floor and the roof is about 30 feet off the ground? A roof with raccoons wandering around on it, in the middle of the night. Huh? Somehow, that just wasn't the first explanation that popped into my head.
I guess there are many types of Colorado mammals who just enjoy a good climb.