NFL warns players about threatening letters

MIAMI (CNN) -- The National Football League has sent letters to players alerting them what to do if they receive an anonymous, threatening letter about interracial relationships.

The FBI has been conducting an investigation into the letters, which were mailed in the last year and a half, CNN has confirmed.

An FBI spokesman said the letters -- about 30 -- have been mailed to both white and African-American athletes, entertainers, civic and community leaders and even a TV personality in Cleveland. Six NFL players on four teams are among those who have received the letters, the bureau said.

"The letters all have a postmark from Cleveland and Youngstown, Ohio; Erie, Pennsylvania; and New Castle, Pennsylvania," FBI Special Agent Robert Hawk told CNN. "They're signed 'Angry White Women' or 'Angry Caucasian Women.'"

The FBI said it does not know what prompted the NFL to send the memo to players recently.

CNN has confirmed the memo was received by Miami Dolphin players and that one of the threatening letters was sent to a well-known Miami Dolphin.

Neither a Dolphin spokesman or the FBI would identify anyone who received one of the anonymous warnings in the mail.

"The letter directs black males to stop relationships with white females or they [the black males] will be castrated or shot or set on fire," Hawk said.

He said the letters were sent to the FBI lab in Washington for analysis "several months ago."

"The letter writer is outrageous," he said. "However, no one's been hurt."

He said the writer's gender is unknown and the targets appear to be indiscriminate.

"The letters are all typewritten, with the same text and margins," Hawk added.

The FBI said the mailings have been received in every region of the country, including the states of Maryland, Florida, and California.

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