Cyberattack constitutes risk to US security, was carefully planned: Biden

US President-elect Joe Biden on Tuesday said the recent massive cyberattack on US companies and federal agencies represents a grave threat to national security and was well planned and carried out.

"This attack constitutes a grave risk to our national security," Biden said at a press conference. "It was carefully planned and carefully orchestrated, it was carried out by using sophisticated cyber tools. The attackers succeeded in catching the federal government off guard and unprepared."

Biden said there is much still unknown about the scope and extent of the damage rendered by the massive cybersecurity breach.