Bicycle detail

The bike was in the communal basement of my home, which is a two flat graystone. To the best of my knowledge, the back gate and back door of the building were locked. When I went downstairs to let my dog out this morning, both the back door and back gate were left wide open. It is unclear how they gained access to the house, as there were no signs of forced entry. The bike was sitting unlocked in the middle of the basement. Luckily, as far as I can tell, nothing else was taken.