The U.S. and U.K. accused state-backed Chinese hackers of targeting politicians, companies and dissidents for years, as well as stealing troves of British voter data, in the latest revelation of cyberattacks that Washington and its allies have linked to President Xi Jinping’s government.

U.S. officials said seven Chinese nationals targeted members of Congress and officials working at the White House and agencies including the Justice Department, as well as candidates, campaign staff and U.S. companies. The hackers, part of a state-sponsored group known as APT31, have been charged with conspiracy to commit computer intrusions and conspiracy to commit wire fraud.

Both the U.S. and U.K. announced sanctions against two of those individuals, as well as a firm in Wuhan, China, called Wuhan Xiaoruizhi Science and Technology. The U.S. alleged it was a front that "has served as cover for multiple malicious cyber operations” and the hackers had worked there as contractors.