The Justice Department announced Monday it has charged two suspected criminal hackers in connection to a wave of ransomware attacks. The two suspected hackers are Ukrainian Yaroslav Vasinskyi and Russian Yevgeniy Polyanin.

“According to the indictments, Vasinskyi and Polyanin accessed the internal computer networks of several victim companies and deployed Sodinokibi/REvil ransomware to encrypt the data on the computers of victim companies,” the Justice Department said in a press release. Vasinskyi is accused of playing a role in “the July 2021 attack against Kaseya, a multi-national information technology software company”. Meanwhile, Polyanin is charged with receiving $6.1 million in payments related to the ransomware attack. The Justice Department says that money has been seized.

“The arrest of Yaroslav Vasinskyi, the charges against Yevgeniy Polyanin and seizure of $6.1 million of his assets, and the arrests of two other Sodinokibi/REvil actors in Romania are the culmination of close collaboration with our international, U.S. government and especially our private sector partners,” FBI Director Christopher Wray said. “The FBI has worked creatively and relentlessly to counter the criminal hackers behind Sodinokibi/REvil.”

In addition to charges related to ransomware attacks, the Treasury Department also announced sanctions against the two charged men.

REvil has been linked in recent months to other ransomware attacks, including one targeting the world’s largest meat processor, JBS SA.

Also on Monday, China had a muted response to satellite images that show the country has built mock-ups of a U.S. Navy aircraft carrier and destroyer in its northwestern desert. The images were captured by Colorado-based satellite imagery company Maxar Technologies over the weekend.

“I’m not aware of the situation you mentioned,” Chinese Foreign Ministry spokesperson Wang Wenbin said in response to a question about the images at his daily briefing Monday.

China has massively upgraded its military in recent years. The country’s capability is increasingly concerning to the United States as tensions rise over the South China Sea, Taiwan and military supremacy in the Indo-Pacific.

In addition, the Pentagon issued a report this month saying China is expanding its nuclear force much faster than U.S. officials predicted just a year ago. According to the report, China could match or surpass U.S. global power by midcentury.