FRANKLIN, Tenn. (WKRN) — A man in Tennessee hid inside a Walgreens store until closing only to tunnel through the drywall of the pharmacy to steal opioids, police said.

According to a release from Franklin police, the man hid inside the store May 18 until after closing time. He waited until all employees left and tunneled into the pharmacy through the drywall to steal a large amount of opioid pain killers, investigators say.

Surveillance video from the Murfreesboro Road Walgreens shows a man in dark shorts, white athletic shoes and an olive T-shirt enter the store during the day. Then, an individual in a similar outfit can be seen wearing a mask and using a flashlight to look through the contents of the pharmacy shelves.

Franklin police are offering an unspecified cash reward to anyone who helps them track down the man seen in surveillance video.

No other information was immediately released.