Shannon Guess Richardson Shannon Guess Richardson

Shannon Richardson, a Texas actress who's had minor roles on The Walking Dead and The Vampire Diaries, was sentenced Wednesday to 18 years in prison for mailing ricin-laced letters to President Obama, then-New York City Mayor Michael Bloomberg and other government officials, The Associated Press reports.

Richardson, 36, who also goes by the stage name Shannon Guess, was also ordered to pay a $367,000 fine.

Walking Dead actress charged with sending ricin letters to Obama

The sentence is the maximum penalty Richardson faced after pleading guilty in December to charges of possessing and producing a biological toxin.

When Richardson was arrested last June, she initially told police that her husband, Nathan Richardson, had mailed the letters. The letter to President Obama reportedly read: "What's in this letter is nothing compared to what ive got in store for you mr president. You will have to kill me and my family before you get my guns. Anyone wants to come to my house will get shot in the face."

Nathan Richardson filed for divorce the day before Shannon was arrested. Their divorce was finalized in January, and Richardson gave birth to a baby, her sixth, last year while in custody.

"The sentiments expressed in those letters were not mine," Richardson told the judge at her sentencing, according to the AP. "I don't feel like I was in my right mind leading up to that point."