Sources tell CBS news they believe Vladimir Putin approved of Russian hacking of U.S. election

American intelligence officials say they are convinced that Russian hacking of the U.S. presidential election was approved by President Vladimir Putin. Sources confirm to CBS news they believe Putin was aware of attacks that began in July of last year. An official investigation is still going on. But this is the first time the hacking that plagued the democratic national committee until election day has been linked to Putin.

• European countries sound the alarm over threat of Russian cyberattacks