A man has been arrested after his elderly mother unknowingly served cannabis brownies during a card game at her senior centre.
Michael Koranda, 46, was arrested on 5 January after reports of a "possible poisoning" at the Tabor Community Center in South Dakota.
The 46-year-old's mother told a sheriff that "her son Michael had baked a pan of brownies and she took them to the community centre card game", police wrote in an affidavit.
Several people then ate the brownies, which had been made using half a pound of cannabis-infused butter.
Koranda's mother was unaware the brownies contained the illicit ingredient when she handed them out.
Police learned her son, who works a teacher, had recently visited Colorado where recreational cannabis is legal for people over 21.
Koranda, who faces a charge of possession of a controlled substance, admitted bringing one pound of cannabis butter into South Dakota to bake the brownies.
He had left them in a tin in the kitchen before going to bed.
Koranda, who lives in Tabor, handed the rest of the butter over to police.
Court records show he was released on a $3,000 (£2,192) bond.