Updated at 3:45 p.m.
Former Trump national security adviser Michael Flynn is invoking his Fifth Amendment right against self-incrimination on Monday, refusing to hand over documents subpoenaed by the Senate Intelligence Committee.
The panel wants to see documents relating to Flynn's interactions with Russian officials as part of its probe into Russia's meddling in the 2016 presidential election.
In a letter to the committee's chairmen, Flynn's attorney Robert Kelner writes, "Producing documents that fall within the subpoena's broad scope would be a testimonial act, insofar as it would confirm or deny the existence of such documents."
The letter also states that Flynn is "the target on nearly a daily basis of outrageous allegations, often attributed to anonymous sources in Congress or elsewhere in the United States Government, which, however fanciful on their face and unsubstantiated by evidence, feed the escalating public frenzy against him."
Flynn was asked to resign from his post in February after it was revealed that he lied to Vice President Pence about his communication with Russia's ambassador to the U.S.
The intelligence committee is one of multiple congressional panels that are looking into Flynn's conduct as well as possible collusion between the Trump campaign and Russia. Flynn has previously sought immunity from what he termed "unfair prosecution" so he could cooperate with the committee.
It's unclear exactly how the committee will respond to Flynn's refusal to hand over the documents. It could hold him in contempt of Congress, but there are other options. Democratic Sen. Dianne Feinstein of California, the ranking member of the Senate Judiciary Committee, says both the intelligence and judiciary committees "should continue to seek other ways to gain access to this information."
She says she and Senate Judiciary Committee Chairman Chuck Grassley of Iowa have sent requests to the White House, FBI and Defense Department "for memos, recordings, notes and other documents."
"The investigation," she vowed in a statement, "will go on."