'Fair Warning': NH Trump Supporter Receives Threatening Letter Ahead Of Election Day

MILFORD, NH (CBS) - She's passionate about her politics that's why Kelly, a Milford New Hampshire resident who doesn't want to use her last name, says her home is all "Trumped out" with signs and flags. But it's apparently made her a target.

Last Saturday she received a threatening letter in the mail that her address is in a database "should Trump not concede the election." It goes on to say that she started this "civil war" and has been given "fair warning."

"It's a surreal moment, you stand there and say what do I think," Kelly said. The letter also tells her to make sure she "has adequate coverage for fire damage."

"You're not just attacking my party or who I represent, you're attacking my home, my family and threatening me with burning down my house," she said.

Identical letters were received through the U.S. mail at two other Milford addresses and two in Brookline, New Hampshire, getting state and federal authorities and the U.S. Postal Service involved. "There is a Manchester postmark and has been sent to a lab for forensic testing and other types of testing," said Lori McCallister a postal service investigator.

"It's very disturbing which is why it raises it right up to felony level criminal threatening," said Capt. Craig Frye of the Milford, New Hampshire Police Department.

The threat is enough that Kelly says the FBI has urged her to install surveillance cameras, police are patrolling the neighborhood and even neighbors are on alert. "It makes me very nervous," said neighbor Judy Green. "I'm looking out the window now and normally I don't pay attention when I'm working from home," Green said.

Even Kelly admits she's looking over her shoulder now, resentful that a letter has made her so fearful in a country so divided. "I feel like it's gone extreme and getting out of control to not even be allowed to speak my first amendment rights," Kelly said. "It's very upsetting to me."

Milford police say stolen lawn signs are usually the crime this time of year. These threats have put entire communities on alert until investigators figure out who is behind them.