I’ve always been a Smarties type, but for some of my kids, who maybe watched the South Park movie at an impressionable age, Skittles brings them to hysterical laughter.

Not so much fun for the two people who ate from a package of contaminated Skittles required hospital treatment for burning throats, cramping and diarrhea, Indiana authorities said Wednesday night.

The Indiana State Department of Health said in a news release that preliminary tests showed that packages of Skittles sold at a Marathon Food Mart in Richmond had some kind of chemical substances, though what exactly those substances were has yet to be confirmed.

Investigators also don’t yet know if the package of candy was tampered with, but Indiana State Police, the Indiana Department of Homeland Security and the U.S. Food and Drug Administration have joined the investigation, Health Department spokesman Amy Reel said.

Authorities are advising people who purchased Skittles with the lot numbers 08JUL14 023 or 01DEC14 023 not to consume the candy but to place the package in an envelope, hold it in a secure location and contact Indiana State Police.