TEXARKANA, Texas (AP) — A Texas woman who had minor acting roles in film and television has been sentenced to 18 years in prison for sending ricin-laced letters to President Barack Obama and former New York Mayor Michael Bloomberg.

Shannon Guess Richardson was sentenced Wednesday by a federal judge in Texarkana, Texas.

The 36-year-old pleaded guilty in December to a federal charge of possessing and producing a biological toxin. Under the plea deal, her attorney said Richardson would serve no more than 18 years.

Prosecutors say Richardson mailed three letters from New Boston, Texas, outside Texarkana, then went to police and claimed that her husband did it.

Richardson was arrested in June 2013. Authorities said she tried to implicate her estranged husband after he filed for divorce.

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