Can you tell which of these are real? These photos keep getting retweeted, reposted, and reused by tricksters.

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WUSA9 talked to one of the foremost researchers of fake photos about why these crop up. But first, let's go through each of these, one by one.

  1. The shark swimming in the carpool lane of a Houston highway? That's fake. This image was from Hurricane Irene in 2011. It's a composite of two different photos.
  2. The alligator on the street is also fake. It was taken near Houston, but back in April which was well before this storm.
  3. The airplanes underwater are an artist’s rendering. The airport pictured isn't one of the two in Houston. It's actually from LaGuardia in New York.
  4. Finally, the family in the refrigerator. It is a real photo. But it’s not from this storm. Once again, this one is from back in April.

Where do these photos come from? WUSA9 talked to Hany Farid of Dartmouth University. He has been looking into internet hoaxes. He says it's tough to know who makes these and that it’s not even clear why they do it.

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The one thing that is clear is that this happens with every major disaster nowadays.

Farid said before posting, check photos on your own. Use a browser like Google Chrome. Right click on the image. Then click "search Google for an image." That will show results for similar images, sometimes even the same one. Usually, a fake photo will come up in old results.