(CNN) -- Police in Northern California have arrested an elementary schoolteacher after she allegedly brought marijuana-laced food to an after-hours employee potluck dinner. Teresa Gilmete Badger, a 47-year-old teacher at Matthew Turner Elementary School in Benicia, was arrested Friday afternoon on suspicion of poisoning after a six-week-long investigation, said Lt. Frank Hartig of the Benicia Police Department. After the late-November get-together in the Bay Area town, several people reported feeling ill, a police statement said.