Real Brainbuster

RE
RIE
REI
RI
?

This found on my door from someone currently harassing me.

Let me give you some background on the situation.

I am currently in a dispute with a neighbor, and he is constantly harassing us
with little notes hanging from our door.

He likes to flaunt the bogus fact that he is "mafia" just because he is Italian American.

This is driving me to insanity to comprehend this message, it is stuck like an annoying song or an unsolved rubix cube.

Recently the trouble escalated with cop calls to shut down an illegal party and a letter delivered to him regarding legal action up to eviction.

I apologize if I am posting in the wrong forum, I am wondering if anyone has any idea what that means. I am asking for your collective knowledge as sort of a beowulf cluster.

Thanks