Is 'possession' real (how about in the USA)?

Possession in the context of one’s body is over taken by another person’s spirit.

Recently,my religion teacher (who is also a theologian) said that possession is real and there are many proof that it’s existed. I can’t accept such irrational perception so I said “It’s fake and done by people that get paid or those who play drama to fool others”. He dismissed my comment and said that “Possession exists everywhere in this world and it has been like that from long time ago”. Then I said “People nowadays don’t believe in such irrational things anymore. Take developed countries,such US as an example,there’s no such thing there. They live better without such issue” (he also has already known that there are many atheists in US). He said that “Possession is also existed in US,it exists everywhere where people have no/less faith”.

I know it’s unnecessary to ask about what is obvious but I need find a fact about whether or not such thing is existing,and is it true that there’s possession in US? (or perhaps this is just his personal opinion)