A few weeks after the 10th anniversary of the Sept. 11 terrorist attacks and one day after a man was arrested and charged in connection with a plot to attack the Capitol, a satirical news site unleashed a brief flash of panic on Twitter.

Around 10:45 a.m. today, the Onion tweeted, “BREAKING: Witnesses reporting screams and gunfire heard inside Capitol building.”

Though tweets shortly thereafter linked to a story showcasing the publication’s trademark irreverence — the piece ran under the headline “Congress Takes Group of Schoolchildren Hostage” — the initial posting was enough for media outlets to call the Capitol Police for more information.

A police spokeswoman released a statement shortly after 11 a.m. to assure the public that nothing had happened.

“It has come to our attention that recent twitter feeds are reporting false information concerning current conditions at the U.S. Capitol,” Sgt. Kimberly Schneider wrote. “Conditions at the U.S. Capitol are currently normal. There is no credibility to these stories or the twitter feeds. The U.S. Capitol Police are currently investigating the reporting.”

The Onion confirmed with Roll Call that the site had not been hacked and that the tweets, which it continued to write into the afternoon, were in connection with one of its main articles of the day.

The fake story describes a “group of armed congressmen” taking 12 children hostage. Related tweets depicted Rep. Trent Franks (R-Ariz.) trying to take down a police helicopter with a shotgun and a recent purchase of “6 semi-automatic handguns, 3 rifles & 600 clips of ammo” by House Majority Leader Eric Cantor (R-Va.).

At around 12:30 p.m., a tweet read: “Congress demanding $12 trillion ransom or ‘all the kids die.’”

Some Hill staffers weren’t amused.

Cantor spokesman Brad Dayspring tweeted, “The Onion: FAIL,” followed by the hashtag “notfunny.”

Another Capitol Hill staffer tweeted, “I just yelled at my coworkers that there was gunfire … you scared the [expletive] out of me.”