Biden says uncertain who is behind latest ransomware attack

The U.S. government's "initial thinking" is that Russian hackers were not behind a sophisticated ransomware attack that hit hundreds of American businesses, President Joe Biden said Saturday.

Biden said "we're not certain" who is behind the attack. "The initial thinking was it was not the Russian government but we're not sure yet," he said.

Biden said he had directed U.S. intelligence agencies to investigate, and the United States will respond if they determine Russia is to blame.