This post was originally published on Mashable.

What's the difference between an elbow and a breast? For Facebook, not much.

The social network recently removed a misleading photo of a woman in a bathtub because it mistook her elbow for a bare breast, according to "Theories of the deep understanding of things".

The Facebook page posted the photo as a way to test Facebook's terms of service, which prohibits the posting of "pornographic" content.

"FB moderators can't tell an elbow from a dangerous, filthy, uncanny and violent female breast," the page said.

"No questions were asked and the post is down."

After realising its blunder, Facebook later restored the photo. In a statement, the company told gossip blog Gawker, "We made a mistake and sent an apology to the original poster."

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- Sydney Morning Herald