Stolen Storage Unit Stuff In The Unit Next To Mine

Yesterday I went to my storage and everything was ransacked. Countless things were broken and thrown about, and I had quite a bit of stuff stolen. My storage unit has an opening on the ceiling and while I was on my own furniture I saw some of my stuff in the unit directly next to mine. How would I legally go about getting my stuff back?

I know for a fact that it's my own stuff, there is no way there would be that many coincidences, when my storage stuff is missing. Also there is an abundance of car parts in that storage and there was a box of air filters left in my storage that definitely isn't mine.