Sen. Rand Paul (R-KY) said Monday that President Obama’s former national security advisor Susan Rice should testify on new reports that she sought to “unmask” the identities of individuals in intelligence reports associated with President Trump.

Paul, on Twitter, called the reports on Rice a "smoking gun."

"I see no legitimate reason for her to be searching a database and unmasking people," Paul said on "America's Newsroom" today.

That's why he's calling on Rice to "testify under oath" about U.S. intelligence activities.

He said that civil libertarians like himself have been warning for years that intelligence agencies are collecting too much data on American citizens.

"Millions of Americans' data and phone calls are in this data bank," Paul said. "We should not let political figures search this data bank for political purpose or for any kind of personal purposes."

"This is a real separation of powers issue. And it shouldn't be happening," he added.

Paul revealed that he raised this issue during his round of golf with President Trump on Sunday.

"The fact that there could be a political figure in the Obama administration that was purposely searching a database, looking for Trump officials, I think confirms exactly what the president said when he said that the Obama administration was doing something nefarious with regard to surveillance on his transition team," Paul said. "And it sounds like they were."

Watch more above, and see Sean Hannity's monologue about the "unmasking" revelations.

UPDATE, 1:00pm ET: In an interview on MSNBC Tuesday, Rice said she asked for the identities of U.S. citizens in intelligence reports, but defended the requests as routine and denied leaking any Trump-related information.

Read more, here.

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