Republican Senator Mark Kirk (IL) says that President Barack Obama should announce the end of the Justice Department's "unwarranted" investigation of CIA interrogators when he visits their headquarters on Friday

"These Americans did their jobs at the direction of the President of the United States and this politically motivated investigation will have a chilling effect on the work of their colleagues and other national security professionals in the U.S. Government," the freshman senator said in a statement.

The Justice Department has been investigating CIA interrogators for alleged abuse of detainees under the Bush administration since 2009. Attorney General Eric Holder said there was enough evidence of abuse to warrant an investigation into whether federal law had been violated, adding it was "the only responsible course of action for me to take."

White House spokesman Jay Carney said Obama was visiting the CIA headquarters in Langley to thank the agency for the work they do to keep Americans safe and "specifically for their excellent work in tracking down Osama bin Laden."

The Associated Press reported that the controversial enhanced interrogations techniques put in place by the Bush administration did not reveal intelligence about Abu Ahmed al-Kuwaiti, the courier that eventually led the U.S. to bin Laden.