IRS: Additional 'inappropriate' screening of groups occurred

The Internal Revenue Service scandal over the targeting of conservative groups just got more complicated.

The agency's temporary head told reporters Monday that he's found evidence of additional "inappropriate" screening lists still in use by agents in Cincinnati to flag certain tax-exempt applications for extra scrutiny.

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A report by the Treasury Department last month said the practice had ended in May 2012.

"There was a wide-ranging set of categories and cases that spanned a broad spectrum," acting IRS chief Daniel Werfel said in a conference call.

He refused to detail those additional criteria, but said he's suspended the use of all such "Be On the Look Out" lists moving forward.

The comments suggest the IRS targeted more than just conservative groups, and that it went on for longer than previously reported.

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The government tax agency has been under fire since May 10, when a senior official publicly apologized for the additional scrutiny. That set off a probe by the Federal Bureau of Investigation and resulted in resignations by top officials and congressional investigations.

Werfel did say an internal IRS review so far has not turned up any "evidence of intentional wrongdoing" inside the agency, nor any involvement by "anyone outside" the agency.

He is scheduled to testify on the report Thursday before the House Ways and Means Committee.