Office of Personnel Management director Katherine Archuleta submitted her resignation on Friday morning in the aftermath of revelations that massive data breaches had occurred under her management.

Archuleta’s departure from OPM followed a previous declaration made late Thursday that she would not resign amidst requests from members of Congress that she step down.

Archuleta’s resignation came after an OPM announcement that was made on Thursday acknowledging that over 21 million Social Security numbers had been compromised due to a data breach. The cyberattack reportedly began in May 2014 and went undiscovered for a year.

Federal Bureau of Investigation Director James Comey said on Wednesday that his own personal information had been compromised in the breach. “I’m sure the adversary has my SF-86 now,” Comey said. “My SF-86 lists every place I’ve ever lived since I was 18, every foreign travel I’ve ever taken, all of my family, their addresses. So it’s not just my identity that’s affected. I’ve got siblings. I’ve got five kids. All of that is in there.”

The culprits have not officially been identified, but administration sources have suggested that Chinese hackers were likely behind the breach.

The most recently announced data breach is separate from, but overlapped, an announcement made in June of a breach affecting the personal information of 4.2 million government employees.