Data hackers stole Social Security numbers, health histories and other data from over 21 million Americans, the Obama administration announced on 9 July. The government also acknowledged that the breach on the US government computer systems was more serious than previously believed, the Associated Press reported.

The breach, believed to be the largest in US history, has risen since it was first disclosed that the Office of Personnel Management's (OPM) personnel database was hacked, resulting in the stolen records of nearly 4.2 million people. According to AP, the Obama administration has since revealed that a second related breach has occurred.

The second breach, which involved the private data of individuals submitted during security clearance background checks, involved 19 million people and 2 million of their spouses, housemates or others. Data hacked included: criminal, financial, health, employment and residency histories, AP revealed.

According to Reuters, because so many of the people were affected by both hacks, a total of 22.1 million people—or nearly 7% of the US population—were affected.

Politicians on both sides of the aisle called for OPM Director Katherine Archuleta's ousting. Republican House of Representatives Speaker John Boehner said President Obama "must take a strong stand against incompetence in his administration and instill new leadership at OPM."

Virginia Democratic Senator Mark Warner agreed, adding, "The technological and security failures at the Office of Personnel Management predate this director's term, but Director Archuleta's slow and uneven response has not inspired confidence that she is the right person to manage OPM through this crisis."

Despite calls for her resignation, Archuleta remained defiant and said she nor OPM chief information officer Donna Seymour would resign, Reuters reported. "I am committed to the work that I am doing at OPM," Archuleta told reporters. "I have trust in the staff that is there."

The White House confirmed that its confidence in Archuleta's leadership remains intact.