The US government reported on Wednesday that about 5.6 million fingerprints in their US personnel records were stolen by hackers.

The 1.1 million fingerprints initially reported to be stolen rose to 5.6 after the Office of Personnel Management discovered that there were additional missing fingerprint records.

The additional 4.5 million fingerprint records were identified to be “part of an ongoing analysis of the data breach by the Office of Personnel Management and the Department of Defense,” notes Reuters. The breach in data has affected records even in the past years.

In a statement issued by the Office of the Personnel Management (OPM) Press Secretary Sam Schumach, he revealed that there is about 21.5 million individuals’ Social Security Identification Numbers and other sensitive information affected by the hacking incident.

Schumach said federal experts believe that “the ability to misuse fingerprint data is limited” but could definitely change over time. He assured the people that their “interagency team will continue to review the impacted data to enhance its quality and completeness, and to monitor for any misuse of the data.”

The Guardian also mentioned that the US believes the OPM was a victim of what they believe was a “Chinese Espionage Operation.” They fear that “any intelligence officer whose prints have been taken would face great risk in operating under an alias because those prints would give away someone’s true identity.”

The Obama Administration, however, remains mum and has not publicly expressed any blame towards China.

The hacking incident happened before the state visit of Chinese President Xi Jinping to Washington.

It was reported in BBC News that China’s President is now in Seattle to begin his three-day meeting with business and technology leaders. After the meetings, he will then proceed to Washington to visit President Barack Obama.

It is expected that Cyber security will be involved in their discussion.