WASHINGTON — Hurrying to check a growing controversy, President Barack Obama ousted the acting commissioner of the Internal Revenue Service late Wednesday amid an outcry over revelations that the agency had improperly targeted tea party groups for scrutiny when they filed for tax-exempt status.

Obama said Treasury Secretary Jacob Lew had asked for and accepted Steven T. Miller's resignation. Obama made no public criticism of Miller but spoke of inexcusable "misconduct" by IRS employees and said new leadership at the agency was critical.

"Americans are right to be angry about it, and I am angry about it," Obama said in a televised statement from the White House. "I will not tolerate this kind of behavior in any agency but especially in the IRS, given the power that it has and the reach that it has into all of our lives."