Now, to the fake tweet that caused havoc from washington to wall street yesterday afternoon. It looked like a bulletin from the associated press reporting an attack on the white house, president obama... See More
Now, to the fake tweet that caused havoc from washington to wall street yesterday afternoon. It looked like a bulletin from the associated press reporting an attack on the white house, president obama injured. Even though it was caught quickly, the fraud showed how much chaos hackers can cause. Jim avila has the the latest from washington. Good morning, jim. Reporter: Good morning, george. It's the tweet that took the hack job from nerdy prank to national security issue. It supposedly came from the trusted associated press. Breaking news. Two explosions in the white house. And barack obama is injure at least for a brief moment in time, people believed that the u.S. Government had been attacked. And the president had been injured. Reporter: Less than 140 characters causing the stock market to drop 150 points. Almost immediately. And sending the white house scrambling to reassure the na I can say that the president is fine. I was just with him. Reporter: Traders and computers reacting to the tweet, programmed to respond to certain words online. Computers don't have emotions. Computers don't have intuition. Computers trade off of one variable and one variable only. Humans use their intuitions. We can look. We can see. We can feel and touch. Looking at this headline right now, we knew pretty quickly it was not a true headline. Reporter: Over the weekend, another media giant had its twitter account compromised. 60 minutes" tweeted exclusive. Terror is striking the usa, and obama is shamelessly in bed with al qaeda, forcing cbs to close its account. Two wspapers, "the new york times" and "the wall street journal," had their firewalls penetrated. Both accused china of spying. Hackers had the first story that we had done about a chinese relative. Reporter: A group took credit for the a.P. Breach, using not sophisticated technology to panic america and wall street with a few key strokes. Earlier this year, michelle obama, the first lady, had her information put on the internet, including her social security and her credit report.
This transcript has been automatically generated and may not be 100% accurate.