How to evict this tenant? (1st eviction) Strange situation in Indiana

[Pedro Oliva]

Ill try my best to explain the situation. So Ive only owned this property for about 3 months now. I am purchasing this on a land contract. It is a duplex and my brother lives in one unit and the owner's nephew in the other. The owner was a payee and handled the tenants social security checks (up until this month of August), so the rent was getting paid on time no problem. 

The tenant was told last month by his uncle that he wanted him out of there since he had suspicion of illegal activities going on there (drugs) and did not want that kind of stuff going on in the house since his name is still on the deed. He's witnessed 15 people there at one point, with many of them asleep there in the middle of a weekday. My brother and cousin witness that random people are going in and out of the place. 

Today me and my brother went in to fix a water leak. Right away I noticed that a couple was living in the living room with blow up mattresses and a  child, another couple with a kid, and a dog were living in the spare bedroom, which explained the dog turds in the yard. As we were leaving another couple showed up, as well as 2 young girls who went in for a few minutes and then back out and yelled something at my girlfriend as we were getting into the car.

He is supposed to be out by tomorrow, his uncle has been wanting him for these reasons and I would like him out as well. I have no lease signed with him as he was already there when i took over the property. I dont think his uncle has a signed lease as well. Im not sure as how to handle this. Any advice as to where to begin? This is my only rental, as Im a wholesaler.