Reid aide divulges details on source of Romney tax claim -- then retracts

FILE: Aug. 7, 2012: Sen. Harry Reid, D-Nevada, at an energy summit at the Bellagio hotel, in Las Vegas, Nevada. (AP)

After days of silence on Harry Reid's disputed claim that Mitt Romney hasn't paid taxes for a decade, a top aide finally spilled details on the supposed source of the allegation -- only to issue a wholesale retraction of those details by Thursday evening.

Reid aide Jose Parra first made the claims in an interview on Los Angeles' KTLK radio, defending his boss' decision to trumpet the tax charge last week on the Senate floor and explaining a bit about the source.

"This person is an investor in Bain Capital, a Republican also, and somebody ... who has been dealing with Romney's company for a long, long time and he has direct knowledge on this," Parra said.

Parra's statement comes after Romney, in an interview with Fox News, challenged Reid to identify his source.

However, after some media attention on Parra's radio interview, Parra issued a statement taking those remarks back.

"I do not know the party affiliation of the source, how long he invested with Bain, or his relationship to Romney beyond the fact that he was an investor with Bain Capital, as Senator Reid has previously stated," he said.

Asked Friday about the mix-up, a Reid aide told FoxNews.com the senator "does not have any plans to reveal further information about the identity of his source."

Romney has denied any suggestion that he hasn't paid taxes for 10 years. He also has rebuffed Democratic calls for him to disprove that suggestion by releasing more than the two years' worth of returns he's provided.

Romney, speaking with Fox News earlier this week, said he doesn't believe Reid has a "credible source. "

Parra said in the radio interview that while Reid is "comfortable" with the source, it's "up to the source" whether to come forward.

The White House has distanced itself from Reid's comment. Still, the Obama campaign is launching an ad that raises those questions about Romney.

"Did Romney pay 10 percent in taxes? Five percent? Zero?" the narrator in the ad asks.