FREMONT, Ind. (WOWO): Fremont police are warning parents to check their kids’ Halloween candy after a Fremont family found nails and thumbtacks in their kids’ haul.

Heather Williams of Fremont, the mom whose Facebook post about the discovery has gone viral, tells WOWO News how they discovered the foreign objects:

“We went around a block and stopped at a church Trunk-or-Treat (in Coldwater, Michigan). The children picked out three treats… my sister got a piece and bit into it,” she says. That’s when her sister discovered a thumb tack.

It appears a few of the candies had been opened, then re-sealed. They also found a nail in a Snickers bar and a tack in a box of Milk Duds.

Police are investigating. The children were not harmed.