Washington (CNN) -- The inspector general who reported Internal Revenue Service targeting of conservative groups said Thursday that he didn't have information until last week that the word "progressive" also was on a list of criteria for extra scrutiny of tax-exempt applications. At a hearing of the House Oversight Committee, Treasury Inspector General for Tax Administration J. Russell George said the information that liberal groups also were probably targeted only came to him July 9. His audit, released in May, cited criteria including "tea party" and other conservative-themed words or labels that were used to decide whether applicants for tax-exempt status should come under further review. Since then, an investigation by the panel turned up documents that showed IRS workers also were told to look for the liberal-themed label.
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NEW: The IRS inspector general says liberal groups also were on target list
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Committee Chairman Issa concedes there is no proof that IRS targeting was political
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Issa is looking for a possible White House role in the targeting
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Democratic Rep. Cummings says Issa is on a partisan witch hunt
@placeholder's audit indicated that lax oversight at the IRS allowed for the singling out of some conservative groups starting in 2010 and continuing until last year.