U.S. prosecutors have charged four Chinese military hackers over the 2017 cyberattack at Equifax, which resulted in a data breach involving more than 147 million credit reports.

The nine-charge indictment was announced Monday against Wu Zhiyong, Wang Qian, Xu Ke and Liu Lei. The Justice Department said the four work for the Chinese People’s Liberation Army. The hackers are said to be part of the APT10 group, a notorious Beijing-backed hacking group that was previously blamed for hacking into dozens of major U.S. companies and government systems, including HPE, IBM and NASA’s Jet Propulsion Laboratory.

Attorney general William Barr said it was the latest in a long line of cyberattacks launched by China, which also included the targeting of health insurance giant Anthem, the Marriott Starwood hotel breach and the U.S. Office of Personnel Management.

“This is the largest theft of sensitive personal identifiable information by state-sponsored hackers ever recorded,” said FBI deputy director David Bowdich, at a presser in Washington, DC.

“Today, we hold [the Chinese military] hackers accountable for their criminal actions, and we remind the Chinese government that we have the capability to remove the internet’s cloak of anonymity and find the hackers that nation repeatedly deploys against us,” said Barr.

Equifax revealed the data breach in September 2017, months after it discovered hackers had broken into its systems.

An investigation showed the company failed to patch a web server it knew was vulnerable for weeks, which let hackers crash the servers and steal massive amounts of personal data. Names, addresses, Social Security numbers and millions more driver license and credit card numbers were stolen in the breach. The data breach also affected British and Canadian nationals.

Equifax chief executive Richard Smith retired shortly after the breach, but didn’t escape criticism. Sen. Chuck Schumer called the breach and the credit giant’s handling of the aftermath “one of the most egregious examples of corporate malfeasance since Enron.”

Equifax later settled with the Federal Trade Commission to pay at least $575 million in fines.

Mark Begor, the credit giant’s current chief executive, said he was “grateful” for the FBI and Justice Department’s work to secure the indictments.

A spokesperson for the Chinese Consulate in New York did not respond to a request for comment.