Letters addressed to inmates at Maplehurst Correctional Complex in Mitlon were seized after staff suspected they were infused with methamphetamine.
Police say an analysis returned positive.
33-year-old Tara McTeer of Kitchener was charged with one count each of trafficking and possession of methamphetamine, police say.
“We know it began in March 2017, and it spanned for several months, and that’s currently still under investigation,” said Staff Sgt. Sloden Lackovic of the Waterloo Regional Police Services.
McTeer is in custody and will be in court next week.
The investigation is ongoing.
