Up to 30,000 missing emails sent by former Internal Revenue Service official Lois Lerner have been recovered by the IRS inspector general, five months after they were deemed lost forever.

The U.S. Treasury Inspector General for Tax Administration (TIGTA) informed congressional staffers from several committees on Friday that the emails were found among hundreds of “disaster recovery tapes” that were used to back up the IRS email system.

“They just said it took them several weeks and some forensic effort to get these emails off these tapes,” a congressional aide told the Washington Examiner.

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The IRS, in a statement provided to the Examiner, said the agency and IRS Commissioner John Koskinen is fully cooperating with the investigation.

"As Commissioner Koskinen has stated, the IRS welcomes TIGTA’s independent review and expert forensic analysis." The IRS statement said. "Commissioner Koskinen has said for some time he would be pleased if additional Lois Lerner emails from this time frame could be found."

Committees in the House and Senate are seeking the emails, which they believe could show Lerner was working in concert with Obama administration officials to target conservative and Tea Party groups seeking tax-exempt status before the 2012 presidential election.

The missing emails extend from 2009 to 2011, a period when Lerner headed the IRS’s exempt-organizations division. The emails were lost when Lerner’s computer crashed, IRS officials said earlier this year.

In June Koskinen told Congress the emails were probably lost for good because the disaster recovery tape holds onto the data for only six months. He said even if the IRS had sought the emails within the six-month period, it would have been a complicated and difficult process to produce them from the tapes.

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The IRS also lost the emails of several other employees who worked under Lerner during that period.

Lerner, who retired from the IRS, has refused to be questioned by Congress.

She provided a statement at a March hearing, but then clammed up, following the advice of her lawyer to avoid self-incrimination.

The House, led by Republicans, voted in May to hold Lerner in contempt of Congress.

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Congressional aides said officials from the inspector general’s office said it could take weeks to get the recovered emails off the tape before sending them to lawmakers in Capitol Hill.

In all, investigators from the inspector general’s office combed through 744 disaster recovery tapes. They are not finished looking.

There are 250 million emails on the tapes that will be reviewed. Officials said it is likely they will find missing emails from other IRS officials who worked under Lerner and who said they suffered computer crashes.

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Investigators said the emails could include some overlapping information because it is not clear how many of them are duplicates or were already produced by Lerner to the congressional committees.

Rep. Darrell Issa, R-Calif., said the House Oversight and Government Reform Committee he chairs will be one of the committees that will examine the emails.

“Though it is unclear whether TIGTA has found all of the missing Lois Lerner e-mails, there may be significant information in this discovery,” Issa told the Examiner. “The Oversight Committee will be looking for information about her mindset and who she was communicating with outside the IRS during a critical period of time when the IRS was targeting conservative groups. This discovery also underscores the lack of cooperation Congress has received from the IRS. The agency first failed to disclose the loss to Congress and then tried to declare Lerner’s e-mails gone and lost forever. Once again it appears the IRS hasn’t been straight with Congress and the American people.”

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