Phoenix police have arrested a woman for using the fake coupons she made at home to defraud Target stores in the Valley.

Detective James Holmes says 51-year-old Terri Darcy made copies of genuine Target coupons allowing her to get many products for free, which she then returned for a full refund. She then allegedly used the cash to fund her heroin habit.

 “The average store clerk, because the coupon actually scans, might not be able to detect that it is counterfeit, even though there are security measures on manufacturer’s coupons to prevent this from happening,” Holmes said.

He says the woman may have hit Target for over $175,000 this year, and possibly more than $300,000 since she allegedly started the scam in 2008.