The Federal Bureau of Investigation said Tuesday it is probing the circumstances surrounding a February audio recording in which aides to Sen. Mitch McConnell discussed how to launch a political attack against actress Ashley Judd, at the time a potential contender for Mr. McConnell's seat.
The recording along with an article was posted Tuesday on the website of the left-leaning magazine Mother Jones.
Mr. McConnell's campaign said it became aware of the recording when called by Mother Jones Monday night.
The Kentucky Republican senator's campaign asked for the FBI probe and criticized the release of the recording, which Mother Jones said was made on Feb. 2 in Louisville.
"There were illegal, immorally made recordings of private meetings at our campaign headquarters," a McConnell campaign spokesman said Tuesday.
Mother Jones said it was provided the tape by someone who wanted to remain anonymous. "It is our understanding that the tape was not the product of any kind of bugging operation," it said in a statement.
An FBI spokesman confirmed the probe but declined to elaborate.
Mr. McConnell is up for re-election in 2014, in a race that is closely watched because he is the highest-ranking Senate Republican. Ms. Judd said last month that she wouldn't run.
The recording of the McConnell strategy session begins with the senator himself saying, "I assume most of you have played the, the game Whac-A-Mole? This is the Whac-A-Mole period of the campaign," to try to identify and attack potential contenders, according to a transcript posted by Mother Jones.
"Unbeknownst to us they were bugging our headquarters—quite a Nixonian move. This is what you get from the political left in America," Mr. McConnell told reporters on Tuesday.
On the audio released by Mother Jones, McConnell aides allegedly laugh about Ms. Judd's mental-health issues, which she has been publicly open about, and discuss how they can be used in a campaign against her.
The Democratic Senatorial Campaign Committee criticized the aides' comments. Mr. McConnell should "apologize to the millions of Americans who suffer from depression and don't believe it's a laughing matter," said the committee's executive director, Guy Cecil. He said Mr. McConnell was "desperate to play the victim."
A spokeswoman for Ms. Judd said, "This is yet another example of the politics of personal destruction that embody Mitch McConnell and are pervasive in Washington, D.C."
Mother Jones also released a recording last year of Republican presidential candidate Mitt Romney talking about the 47% of Americans who were "dependent on government."
—Devlin Barrett
contributed to this article. Write to Siobhan Hughes at siobhan.hughes@dowjones.com
