LOS ANGELES, CA (Catholic Online) - Those who received the letters say their citizenship is being challenged, along with their eligibility to vote.

FBI Spokesman David Couvertier said his office opened up an investigation receiving reports that eligible voters throughout Florida received the letters.

"We're taking it as a serious situation," he said. "We're looking at everything from civil rights violations to election fraud -- to everything in between."

"We believe these letters appear to meet the standard of voter intimidation," Spokesman for the Florida Secretary of State Chris Cate says. Between 50 and 100 such letters have been reported thus far, "and those are only the ones we know about. We're encouraging people to come forward."

The letters began turning up in mailboxes late last week. The bogus messages have been sent under the names of real Florida county election supervisors, with some correct contact information informing the voters that the supervisors have received "information" about their citizenship status, "bringing into doubt your eligibility as a registered voter."

The letters then instruct the voter to fill out a Voter Eligibility Form in the next 15 days. Failure to do so will result "in the removal of your name from the voter registration rolls and you will no longer be eligible to vote.

"A non-registered voter who casts a vote in the state of Florida may be subject to arrest, imprisonment, and/or other criminal sanctions," the letters state.

Florida, a key battleground state for the upcoming presidential elections, contains many divergent opinions among the electorate.

Couvertier says that some of the letters have been received by "longtime, staunch voters who have been exercising their right to vote" for years. "Our concern is someone who might not be secure and then questions whether they should vote."

It's not clear who sent the letters, which were machine postmarked in Seattle. Couvertier says that the FBI in Tampa is working with its Seattle office to track down the perpetrator.

A "significant majority have gone to Republican voters, but not exclusively. We've got Democrats who received the letters, we've got independents. We're telling everybody to be on the lookout," Cate says.

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