US President Barack Obama on Wednesday authorized imposing economic sanctions on US and foreign computer hackers who engage in cyber-attacks and cyber-espionage on US targets. "Cyber-threats pose one of the most serious economic and national security challenges to the United States, and my administration is pursuing a comprehensive strategy to confront them," the president said. The authorization gives the US Treasury secretary the ability to sanction "individuals or entities" that pose a cyber-threat to the "national security, foreign policy, or economic health or financial stability of the United States," Obama said.