First, Hillary Clinton. Now, Dianne Feinstein.

A crowd of President Donald Trump's supporters at an Iowa rally Tuesday began the familiar refrain – normally reserved for Trump's 2016 opponent – after Trump mentioned the California Democratic senator.

The president was taking a number of Democratic senators to task, who he said have gone "wacko," when he got to Feinstein. He accused the top Democrat on the Senate Judiciary Committee of leaking "the documents," presumably referring to the theory that her office leaked the letter containing Christine Blasey Ford's sexual assault allegation against Supreme Court Justice Brett Kavanaugh to the news media.

"How about Sen. Feinstein? That's another beauty," Trump said. "Did you leak the documents?"

"'Huh, what? What? No, I didn't ... '" the president asked in an apparent attempt to mockingly parody Feinstein.

Trump, who has called Democrats "an angry left-wing mob," then turned to the crowd for judgment, asking, "Did we leak?"

"Did we leak?" he repeated, pointing to an audience member.

"He just said, 'No, we didn't leak,'" Trump said, laughing.

At the point, the crowd began a thunderous chant of "Lock her up!" in unison.

Trump paused for a moment before saying, "And I think they're talking about Feinstein. Can you believe it?"

The chant has typically been aimed at Clinton for her use of a private email server to conduct official business during her tenure as secretary of State during the Obama administration. Critics say her actions put classified material at risk, but an FBI investigation did not find that her actions warranted criminal charges.

Feinstein has been criticized by Republicans and Democrats for not sharing Ford's allegations sooner. The California Democrat did pass the letter along to the Justice Department in September but she has denied that she or anyone in her office gave Ford's letter to reporters.

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