Maria Bassi Lauro, a former teacher, has pleaded guilty to sending packages with a suspicious powder to employees of four elementary schools that fired her, a press release from the U.S. Attorney’s office says. The 66-year-old woman sent mail containing a suspicious, unidentifiable powder to the four elementary schools in Central Florida beginning in August 2018, specifically to faculty members that had a role in her terminations. Lauro’s plea agreement reveals that she hoped the recipients would think they had been exposed to a fatal substance, and in three of the mailings, she left a note that implied they faced “punishment.” Authorities ultimately determined the powder was baking soda. The case is still being prosecuted, but Lauro faces up to 15 years in federal prison.