WASHINGTON (CBSNewYork) — Sally Yates, a top Justice Department official in the Obama administration, is set to testify Monday about President Donald Trump’s dismissed national security adviser.

As CBS2’s Jessica Moore reported, Yates was fired by the Trump administration in January after refusing to defend the president’s travel ban in court as acting attorney general.

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Ahead of Monday’s Senate Judiciary hearing on Russia, Trump focused on Democrats Sunday morning, referencing the “fake” media and saying Democrats’ dealings with Russia warrant attention.

Yates will testify for the first time Monday about her warnings to the Trump White House about former National Security Adviser Gen. Michael Flynn.

“She apparently has some information as to who knew what when, that she is willing to share,” said U.S. Sen. Dianne Feinstein (D-California) a member of the Senate Judiciary Intelligence Committee, “and that would be what she knew about Michael Flynn’s connections to Russia.”

Sen. Roy Blunt (R-Missouri) said Flynn’s contacts are not suspicious – but lying about it is.

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“What was particularly wrong was General Flynn was not being truthful about the substance of what he said,” Blunt said.

Meanwhile, Trump’s son-in-law and adviser Jared Kushner is facing questions about conflicts of interest, as reports emerged that his sister, Nicole Meyer, spent the weekend promoting the family business and controversial EB-5 visas in China.

The visas grant wealthy foreigners and their families a conditional two-year green card after investing at least $500,000 in U.S. businesses.

In a statement, his personal attorney told CBS News that Kushner “has no involvement” with his previous companies, “divested his interests,” and is not a beneficiary of the family trust.

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A Kushner companies representative also sent CBS News a statement apologizing on behalf of Meyer, if “mention of her brother was in any way interpreted as an attempt to lure investigators.”