Nearly 20 black families in one Eastpointe neighborhood received viscous, threatening letters Tuesday telling them they need to "move across 8 Mile."

"We tired of u n------ keep movin in are neighborhood!!" read the letter. "you need to move across 8 mile. we just need to start killing you n------ one by one!"

While the spelling, grammar and underlying message of the letter reveal an astounding level of ignorance, it's clear the hate-monger did his or her research: Below the message the sender included a list of addresses where black families live in the neighborhood on Sprenger Street, just four blocks north of 8 Mile.

"I'm scared now because I just don't know because someone really did their homework, and that's my main concern," Kwanita Graham, a local mother who received the letter,

.

But the sender won't be receiving any passing grades for that homework. He or she managed managed to target at least one white woman -- who like her neighbors was shocked and called the police -- and may have committed a federal crime by sending a death threat through the mail.

Eastpointe Police and U.S. Postal Inspectors are investigating. They're trying to determine where the letters were sent from and testing envelopes for fingerprints or DNA that could lead them to the suspect.

It's the latest in a string of racially-charged incidents involving black families in the Metro region. Back in March, families in Auburn Hills woke up to find

in their front lawns. And in June, three Independence Township men received jail time for

in the yard of a black family in 2009.