Republican presidential candidate Nikki Haley on Thursday blamed a Democrat “plant” as the cause of an embarrassing exchange during a town hall in which she failed to mention slavery when asked about the causes of the Civil War.

The former South Carolina governor was roundly criticized for her answer at the event in New Hampshire on Wednesday in which she claimed the conflict was about “how government was going to run” and “the freedoms and what people could and couldn’t do.”

In an apparent effort to quell the backlash, Haley used a radio appearance Thursday morning to clarify her beliefs—and accuse the voter who asked her about the Civil War as being some kind of Democratic operative.