I worked for a building materials company at their warehouse, which was a very old one and in a remote area. I had heard stories about stuff moving and strange sounds at nights, from the workers on the floor.
Once I was working along late at night, although these stories never bothered me but that feeling was there in the back of my mind that this place has had some weird shit going on. I dismissed it as my mind playing games on me because of the knowledge that this place is haunted. I got up to get some file from the cabinet and when I returned to my desk, there were 3 manila envelopes neatly arranged on the desk. I was pretty sure that there was no one else there apart from me, everyone had left. First thing came to my mind was that some ones is playing a prank. So I ran up to the switches and turned on all the lights and then ran to the security guards room where he was having dinner. I asked him if anyone had entered the warehouse since close of work or anyone was still there inside. He keeps a log of any visitors coming and going and also has access to the log in log out records that are saved automatically when an employee swipes their cards at various locations inside the warehouse, including when they enter or leave it.
After reviewing the logs and checking the cameras we came to the conclusion that there was no one there except for me and the guard. I was walking back to my desk with each step the small voice in my mind telling me to turn around and just go, but I had to find out how the envelopes got there and what is in them. I cautiously open the door to my room, the hair on my neck and back standing upright at this moment. I glance on the desk and the envelopes are not there and my desk is a mess with all the papers strewn on the ground. I just turn around and decide enough work for today and head home.
The office area where employees sit is not under cctv coverage, only the entrance is, so could not have seen what or whoever had done this and I will never know.