Hacked Associated Press Twitter Feed Sends Erroneous Message About Explosions at White House .. Markets Plummet

(Hacked AP Twitter account .... )

(Stock Market reactions ... ) 

"The Twitter account of The Associated Press was hacked on Tuesday and erroneously sent out a tweet saying there had been explosions at the White House, injuring President Obama.

Within a few minutes, Twitter suspended the account, and Julie Pace, the chief White House correspondent for The A.P., announced at a White House briefing that the account had been hacked. Jay Carney, Mr. Obama’s press secretary, confirmed that the president was unharmed. 

Editors at The A.P. soon followed with a statement saying that “The (at)AP twitter account has been hacked. The tweet about an attack at the White House is false. We will advise more as soon as possible.”
The Dow Jones industrial average plummeted more than 150 points when the news broke on Twitter — an indicator of traders’ presence on the social media platform — before immediately recouping the losses after it became clear that there had been no incident at the White House." NY Times Blog