(NBC) — A Jewish teen’s birthday party went from fun to offensive after two attendees decided to decorate their cupcakes with swastikas.

The photograph was posted on social media by the parent who threw the party.

The mother posted the pictures in hopes of turning the horrible mistake into a teachable moment.

According to the post, the girls decorated their cupcakes with the offensive symbol because they thought it was funny.

The teens have since apologized, and according to the social media post, their parents have also explained to the teens why this symbol is so offensive.