Bloomberg graphic showing a sharp plunge in the S&P 500 after a fake AP tweet about a terrorist attack on the White House | Bloomberg/YouTube

The tweeted message originated from the official @AP Twitter account shortly after 1 p.m. eastern time and reported twin explosions at the White House which left President Barack Obama injured. The Dow dropped nearly 143 points in just three minutes after the fake tweet was sent. It regained its losses in just a few minutes, but the crash is a frightening example of how vulnerable stocks are to news of terrorist activity.

Tweet sent by a hacked AP Twitter account | AP

A group calling itself the Syrian Electronic Army has claimed responsibility for the hack. The SEA is a pro-regime element in Syria that uses DDos attacks and phishing scams to fight opposition forces and their supporters.

The Associated Press has announced that it is suspending its Twitter accounts.