After the Internal Revenue Service issued an apology Friday for "inappropriate" targeting of conservative and tea party groups during the 2012 election, U.S. Rep. Michele Bachman issued a statement calling the practice a "stunning abuse of power."

IRS employees singled out organizations that included the words "tea party" or "patriot" in their applications for additional reviews to see if they were violating their tax-exempt status.

Denying the probes were politically motivated, the IRS said low-level employees in Cincinnati initiated the reviews. Agency officials also said a George W. Bush appointee was leading the agency when the queries were made.

"It is outrageous that the IRS has admitted to intimidating and targeting Tea Party and conservative organizations because of their political beliefs," wrote Bachmann, chairwoman of the congressional Tea Party Caucus.

"This is a stunning abuse of power and the American people deserve answers as to who authorized it -- it is hard to believe this was a 'low-level' decision."

Roughly 75 groups were targeted. None had their tax-exempt status revoked, the IRS said.

Several prominent Republicans, including House Majority Leader Eric Cantor, have vowed to launch investigations.

Bachmann and U.S. Rep. John Kline joined dozens of Republican lawmakers in signing a letter to former IRS Commissioner Douglas Shulman in April 2012, accusing the agency of disparate treatment of conservative political groups.

Here's a copy of the letter.

April 232012 Irs Letter