Three-quarters of US OPM hack victims still in dark

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Millions More Americans Hit by Government Hack

WASHINGTON (Reuters) -- Fewer than a quarter of 21 million federal workers hit by a major computer hack have been officially told that their personal information was compromised, six months after the breach was detected, a U.S. government official said on Tuesday.

About 5 million notifications about the hack have been sent out so far, a spokesperson for the U.S. Office of Personnel Management (OPM) told Reuters in an email.

SEE ALSO: Cybersecurity expert reveals the biggest threats facing the US

The slowness of the notification process underscores Washington's struggles in dealing with its computer vulnerabilities, a growing problem that the Obama administration has been trying to address.

After it fell victim to two successive cyberattacks, both begun in 2014 and revealed earlier this year, OPM was roundly criticized by lawmakers for its response.

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Three-quarters of US OPM hack victims still in dark
Katherine Archuleta, director of the Office of Personnel Management, listens during a hearing of the Senate Homeland Security and Governmental Affairs Committee on Capitol Hill June 25, 2015 in Washington, DC. Witnesses testified about the hacking of Office of Personnel Management data. (Photo credit: BRENDAN SMIALOWSKI/AFP/Getty Images)
From left Katherine Archuleta, director of the Office of Personnel Management, US Chief Information Officer Tony Scott, Assistant Homeland Security Secretary for National Protection and Programs Andy Ozment, and McFarland, inspector general of the Office of Personnel Management, are sworn in during a hearing of the Senate Homeland Security and Governmental Affairs Committee on Capitol Hill June 25, 2015 in Washington, DC. Witnesses testified about the hacking of Office of Personnel Management data. AFP PHOTO/BRENDAN SMIALOWSKI (Photo credit should read BRENDAN SMIALOWSKI/AFP/Getty Images)
UNITED STATES - JUNE 23 - Katherine Archuleta, director, Office of Personnel Management, testifies during a Senate Appropriations Financial Services and General Government Subcommittee hearing to review data security and information technology spending at the Office of Personal Management on Capitol Hill on Tuesday, June 23, 2015. (Photo By Al Drago/CQ Roll Call)
WASHINGTON, DC - JUNE 23: Katherine Archuleta, director of Office of Personnel Management, arrives for a Senate Appropriations Financial Services and General Government Subcommittee hearing to review information technology spending and data security at the U.S. Office of Personnel Management, on Capitol Hill, June 23, 2015 in Washington, DC. FBI Director James Comey recently told Senators in a closed-door meeting that the personal data of an estimated 18 million current and former federal employees were affected by a recent cyber breach at the Office of Personnel Management. (Drew Angerer/Getty Images)
White House Press Secretary Josh Earnest answers questions on the massive cyber-attack on the personal data of government employees June 5, 2015 during the daily briefing in the Brady Briefing Room of the White House in Washington, DC. The US government on Thursday admitted hackers accessed the personal data of at least four million current and former federal employees, in a vast cyber-attack suspected to have originated in China. AFP PHOTO/Mandel NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images)
White House Press Secretary Josh Earnest answers questions on the massive cyber-attack on the personal data of government employees June 5, 2015 during the daily briefing in the Brady Briefing Room of the White House in Washington, DC. The US government on Thursday admitted hackers accessed the personal data of at least four million current and former federal employees, in a vast cyber-attack suspected to have originated in China. AFP PHOTO/Mandel NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images)
A gate leading to the Homeland Security Department headquarters in northwest Washington, Friday, June 5, 2015. China-based hackers are suspected once again of breaking into U.S. government computer networks, and the entire federal workforce could be at risk this time. The Department of Homeland Security said in a statement that data from the Office of Personnel Management _ the human resources department for the federal government _ and the Interior Department had been compromised. (AP Photo/Susan Walsh)
White House Press Secretary Josh Earnest answers questions on the massive cyber-attack on the personal data of government employees June 5, 2015 during the daily briefing in the Brady Briefing Room of the White House in Washington, DC. The US government on Thursday admitted hackers accessed the personal data of at least four million current and former federal employees, in a vast cyber-attack suspected to have originated in China. AFP PHOTO/Mandel NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images)
WASHINGTON, DC - JUNE 05: The Theodore Roosevelt Federal Building that houses the Office of Personnel Management headquarters is shown June 5, 2015 in Washington, DC. U.S. investigators have said that at least four million current and former federal employees might have had their personal information stolen by Chinese hackers. (Photo by Mark Wilson/Getty Images)
WASHINGTON, DC - JUNE 05: The entrance to the Theodore Roosevelt Federal Building that houses the Office of Personnel Management headquarters is shown June 5, 2015 in Washington, DC. U.S. investigators have said that at least four million current and former federal employees might have had their personal information stolen by Chinese hackers. (Photo by Mark Wilson/Getty Images)
WASHINGTON, DC - JUNE 05: The Theodore Roosevelt Federal Building that houses the Office of Personnel Management headquarters is shown June 5, 2015 in Washington, DC. U.S. investigators have said that at least four million current and former federal employees might have had their personal information stolen by Chinese hackers. (Photo by Mark Wilson/Getty Images)
White House press secretary Josh Earnest speaks about the Chinese hack of the computer system of the Office of Personnel Management, Friday, June 5, 2015, during the daily press briefing at the White House in Washington. (AP Photo/Evan Vucci)
Graphic shows details of recent notable data breaches by organization; 3c x 6 inches; 146 mm x 152 mm;
FILE - This Feb. 24, 2015, file photo, shows the Homeland Security Department headquarters in northwest Washington. The Department of Homeland Security said in a statement Thursday, June 4, 2015, that data from the Office of Personnel Management and the Interior Department had been hacked. (AP Photo/Manuel Balce Ceneta, File)
The American flag is reflected in a window at the Theodore Roosevelt Building, headquarters of the U.S. Office of Personnel Management (OPM), in Washington, D.C., U.S., on Friday, June 5, 2015. The disclosure by U.S. officials that Chinese hackers stole records of as many as 4 million government workers is now being linked to the thefts of personal information from health-care companies. The hackers, thought to have links to the Chinese government, got into the OPM computer system late last year, according to one U.S. official. Photographer: Andrew Harrer/Bloomberg via Getty Images
Vehicles drive past the Theodore Roosevelt Building, headquarters of the U.S. Office of Personnel Management (OPM), in Washington, D.C., U.S., on Friday, June 5, 2015. The disclosure by U.S. officials that Chinese hackers stole records of as many as 4 million government workers is now being linked to the thefts of personal information from health-care companies. The hackers, thought to have links to the Chinese government, got into the OPM computer system late last year, according to one U.S. official. Photographer: Andrew Harrer/Bloomberg via Getty Images
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OPM had no immediate additional comment on the matter on Tuesday, or on its expected notification timetable ahead.

Officials have privately blamed China for the OPM breach.

The Defense Information Systems Agency in September awarded a $1.8 million contract to Advanced Onion, a technology firm, to help locate and notify victims of the OPM breach, which exposed names, addresses, Social Security numbers and other sensitive information of current and former federal employees and contractors. About 5.6 million fingerprints were pilfered, an upwardly revised number from an initial estimate of 1.1 million.

The notification process for the smaller of the two breaches, which affected 4.2 million individuals, raised alarm when victims were asked to follow instructions online in prompts that some said resembled phishing scams. Others complained of long wait times with support call centers. That episode prompted the government to pursue Advanced Onion to deal with the larger breach, a process that took several months.

It has been six months since the larger OPM hack was detected, and more than a year and a half since hackers first infiltrated the agency's databanks.

In July, OPM Director Katherine Archuleta resigned amid growing scrutiny of the agency's cybersecurity practices and its ability to respond to the breaches.

Officials have offered three years of credit monitoring and identify-theft monitoring services to hacked employees.

Despite the precaution, a prominent cybersecurity researcher said on Monday there was no indication any hacked OPM data was for sale on the black market, reaffirming the likelihood that the hackers were working for a foreign country.

RELATED: Notable data breaches

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Three-quarters of US OPM hack victims still in dark
LONDON, ENGLAND - AUGUST 19: A detail of the Ashley Madison website on August 19, 2015 in London, England. Hackers who stole customer information from the cheating site AshleyMadison.com dumped 9.7 gigabytes of data to the dark web on Tuesday fulfilling a threat to release sensitive information including account details, log-ins and credit card details, if Avid Life Media, the owner of the website didn't take Ashley Madison.com offline permanently. (Photo by Carl Court/Getty Images)
The Homeland Security Department headquarters in northwest Washington, Friday, June 5, 2015. China-based hackers are suspected once again of breaking into U.S. government computer networks, and the entire federal workforce could be at risk this time. The Department of Homeland Security said in a statement that data from the Office of Personnel Management _ the human resources department for the federal government _ and the Interior Department had been compromised. (AP Photo/Susan Walsh)
FILE - In this Feb. 5, 2015 file photo, the Anthem logo hangs at the health insurer's corporate headquarters in Indianapolis. Insurers aren't required to encrypt consumers' data under a 1990s federal law that remains the foundation for health care privacy in the Internet age _ a striking omission in light of the cyberattack against Anthem, the nation's second-largest health insurer. (AP Photo/Michael Conroy, File)
Sony Pictures Entertainment headquarters in Culver City, Calif. on Tuesday, Dec. 2, 2014. The FBI has confirmed it is investigating a recent hacking attack at Sony Pictures Entertainment, which caused major internal computer problems at the film studio last week. (AP Photo/Nick Ut)
FILE - In this file photo made Oct. 6, 2009, employee John Abou Nasr pushes shopping carts in the parking lot of a Home Depot in Methuen, Mass. Home Depot's data breach could wind up being among the largest ever for a retailer, but that may not matter to its millions of customers. (AP Photo/Elise Amendola, File)
Shoppers arrive at a Target store in Los Angeles on Thursday, Dec. 19, 2013. Target says that about 40 million credit and debit card accounts may have been affected by a data breach that occurred just as the holiday shopping season shifted into high gear. (AP Photo/Damian Dovarganes)
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