Trending on Twitter isn’t always a good thing.

The New York Police Department found that out the hard way when it invited its followers to post photos of themselves with the boys in blue and hashtag it #myNYPD.

Some posted pleasant, smiling photos. Others, not so much. (You know know where this is going.)

Photos of police brutality took over the hashtag. Some had creative captions, and some photos were disturbing.

Despite the hashtag hijacking, the NYPD is holding its head high.

NYPD spokesperson Deputy Chief Kim Y. Royster told the The New York Times that the department was "creating new ways to communicate effectively with the community" and that Twitter provided "an open forum for an uncensored exchange" that is "good for our city."

The NYPD's hashtag snafu is only the latest incident of its kind. This past November, JPMorgan Chase introduced a #AskJPM hashtag for a live chat that quickly turned into a peg for harsh criticism and led the bank to cancel the chat altogether. In perhaps a more memorable incident, McDonald’s rolled out an #McDStories campaign in early 2012 that was supposed to inspire customers to share positive stories about their experiences at the fast-food chain, but instead inspired stories about food poisoning and vomiting.

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