GOP presidential frontrunner Donald Trump is blaming an intern for a retweet posted to his Twitter page early Thursday that some found offensive to Iowans.

The retweet, which was deleted shortly after, read: “@mygreenhippo #BenCarson is now leading in the #polls in #Iowa. Too much #Monsanto in the #corn creates issues for the brain? #Trump #GOP”

Trump was quick to clarify that a “young intern” was responsible for the retweet and that they were sorry.

The retweet mishap comes the same day a new Quinnipiac University poll came out with Ben Carson leading Donald Trump 28% to 20%.

Fox News' Christopher Snyder contributed to this report.