A Twitter campaign that was supposed to reveal positive stories from McDonald's suppliers turned into a nasty hashtag hijacking, as unhappy customers tweeted a variety of unpleasant tales — such as finding fingernails in their food.

The hashtag #McDStories started last week with a few tweets from the brand, promoting tales from suppliers. "Meet some of the hard-working people dedicated to providing McDs with quality food every day #McDStories http://t.co/BoNIwRJS," one of the tweets said.

What ensued was less laudatory. "I haven't been to McDonald's in years, because I'd rather eat my own diarrhea," read one. "One time I walked into McDonald's and I could smell Type 2 diabetes floating in the air and I threw up," said another.

In an interview with PaidContent, McDonald's social media director Rick Wion, said, inevitably "fans and detractors will chime in." That they did.

“Within an hour, we saw that it wasn’t going as planned,” said Wion. “It was negative enough that we set about a change of course."

Check out the video above to learn more about the fiasco. How do you think McDonald's could have handled this differently? Was there any way to stop the damage? Share your thoughts in the comments.