The Veterans Affairs data analyst who lost the personal data of 26.5 million veterans improperly took the information home for three years before the data was stolen, government investigators told Congress Thursday.

In a pair of hearings, VA Inspector General George Opfer detailed a series of missteps leading to one of the nation's largest information security breaches. He noted that his office only became aware of the May 3 burglary through office gossip.

"We were never notified," Opfer told Senate and House panels investigating the breach, explaining that one of his employees first heard about a burglary -- and that VA electronic records may have been stolen -- while attending a routine meeting on May 10.

Click here to read the statement disclosing the theft by the Department of Veterans Affairs.

"It wasn't until we interviewed the employee on the 15th that we knew we had a significant problem" involving a vast cache of Social Security numbers, birthdates and disability ratings, Opfer said. Only then did the VA bring in local and federal law enforcement to investigate.

The disclosure comes as the VA is under attack for a three-week delay in publicizing the burglary. During the hearing, VA Secretary Jim Nicholson said he was "mad as hell" that employees did not tell him about the breach until May 16.

He acknowledged that Deputy Secretary of Veterans Affairs Gordon Mansfield knew immediately about the incident. But he declined to say whether Mansfield would be fired or how the theft could have happened, citing the need to await results of a full investigation.

"As a veteran, I am outraged. Frankly I'm mad as hell," Nicholson said. "I can't explain the lapses of judgment on the behalf of my people. We will stay focused on these problems until we get them fixed."

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Lawmakers were skeptical.

"The testimony you gave us is absolutely baffling," said Sen. Susan Collins, R-Maine, who chairs the Homeland Security Committee. "You seem to be saying it was just one employee. But it's not just one employee. You have a high-risk vulnerable system that has been identified time and again as vulnerable."

At the House hearing, Rep. Bob Filner, D-Calif. was even more blunt.

"Your own people don't tell you about the theft involving 26 million veterans. You say you take responsibility but then you tell veterans to go call your creditors," he said.

"You're not taking responsibility for this mismanagement debacle," Filner said. "The most dramatic thing to take responsibility is to resign."

White House press secretary Tony Snow said Thursday that wasn't going to happen.

"He'll have his opportunity to testify on Capitol Hill today," Snow said of Nicholson. "I'm sure they will have sharp questions for him. But he's not tendering his resignation."

Congress is trying to determine whether the VA had adequate security measures in place to guard against the unauthorized disclosure of veterans' Social Security numbers and birthdates. It is one of the nation's largest security breaches.

Also at issue is why the department waited so long before acknowledging that a government-owned laptop and disks were stolen in what appeared to be a routine burglary at an agency analyst's home in Maryland.

During the hearing, Rep. Steve Buyer, R-Ind., chairman of the House veterans panel, pressed Nicholson to give the nation's veterans assurances that their information will not be used for identity theft, or that they would be "made whole" if the information is misused.

Nicholson said he could not, saying that the VA would have to get more funding to compensate veterans. Nicholson has previously downplayed the potential danger, explaining that the May 3 theft appeared to be a random burglary.

"Before I can give you that assurance, I have to work with Congress ... if they suffer a loss," Nicholson said, who added that it would take about $25 million alone to improve security procedures at his agency. "It will give piece of mind to veterans if they suffer a loss to have a system to compensate."

Nicholson got an endorsement from President Bush even as lawmakers pressed for greater accountability and awaited answers in the hearings and a subsequent joint meeting of the Senate Veterans' Affairs and the Homeland Security and Governmental Affairs committees.

Snow said Wednesday said Bush had "full faith and confidence" in Nicholson. Snow originally had declined to issue a statement of support in the president's name, but then said he wanted to clarify his remarks.

Nicholson is a Vietnam War veteran and former chairman of the Republican National Committee.

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