The Washington Post revealed that the New York Daily News and the Associated Press both fell for an online parody group’s claim that they placed those mysterious white flags atop the Brooklyn Bridge.

The Daily News reported that a “pro-cycling group” had taken responsibility for having removed American flags atop the towers of the Brooklyn Bridge and replaced them with white flags. That “pro-cycling group,” the story reported, was the Bicycle Lobby, which had tweeted: “Earlier today we hoisted two white flags to signal our complete surrender of the Brooklyn Bridge bicycle path to pedestrians.”
The corrected version of the story was a little different: “A parody group, the Bicycle Lobby, joked that it hung the white flags to signal surrender of the bridge’s bicycle path to pedestrians.” 
At the AP, when they realized they had made the same mistake (it’s been a bad week for the Associated Press), they sent this alert to editors across the nation and across the globe: “The Associated Press has withdrawn its story about bike path advocates taking responsibility for the appearance of two mysterious white flags on the Brooklyn Bridge. The claim of responsibility has not been verified. A corrected version will be published imminently.”
Meanwhile, the Post noted that the folks at Bicycle Lobby had a lot of fun with their undeserved status as a potent force in the everyday news cycle.
Here’s a tweet they sent:
Stop us if you’ve heard this one before. How many Daily News reporters does it take to not fact-check a story?

And here’s another:

If you believe we’re for real, we have a bridge in Brooklyn we’d like to sell you.
And just to rub it in, they pointed out that their Twitter page (featuring a bicycle in a lobby) is quite straightfoward in describing their social media role:
To be fair, we don’t reveal we’re a parody account until the second line of our profile.