Internal Revenue Service Commissioner John Koskinen (KOSS-kuh-nenn) is telling Congress that eight federal employees connected to the tea party investigation experienced hard drive crashes.
Koskinen says it's not clear whether all eight of the hard drive crashes resulted in lost emails.
In the past week the IRS acknowledged it can't produce emails from some of the officials connected to the investigation. Among the missing emails are those from former IRS executive Lois Lerner, who is at the center of the probe. Her computer crashed in 2011.
Koskinen says the IRS took additional steps to retrieve Lerner's data but was unsuccessful.
Koskinen is testifying before the House Ways and Means Committee. He says the IRS will provide more of Lerner's emails to Congress today.
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