Fox has learned that U.S. Capitol Police have ended an inquiry into a satire by The Onion, which issued fake reports that members of Congress were taking schoolchildren hostage in the Rotunda.

At approximately 10:30 a.m. ET Thursday, the Onion tweeted "BREAKING: Witnesses reporting screams and gunfire heard inside Capitol building." This was followed by, "BREAKING: Capitol building being evacuated. 12 children held hostage by group of armed congressmen." And then, "Congress Takes Group Of Schoolchildren Hostage," which linked to a write-up of a fake news report on their website and included a doctored image of House Speaker John Boehner holding a gun to the head of a young girl on the Capitol steps.

Fox has learned that when Capitol Police became aware of the reports of an incident, which exploded on Twitter and other social media, security personnel alerted appropriate figures including the Congressional leadership that the reports were false.

Immediately following the flurry of false reports, U.S. Capitol Police spokeswoman Kimberly Schneider indicated her department was taking the matter seriously.

"It has come to our attention that recent twitter feeds are reporting false information concerning current conditions at the U.S. Capitol. 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."

A source familiar with the matter says the police are no longer probing the incident.