Updated at 11:55 a.m. ET
A senior FBI official said Wednesday the nation is "under relentless assault" from foreign adversaries, as the Senate Judiciary Committee continued its probe into Russia's interference with last year's presidential election.
Bill Priestap, assistant director of counterintelligence at the FBI, painted a bleak picture of efforts — both overt and covert — by foreign government agents inside the U.S. "Our economy, our national security and our way of life are being actively threatened by state actors and their proxies," he said.
Wednesday's committee hearing was focused on the Foreign Agents Registration Act.
Committee Chairman Sen. Charles Grassley, R-Iowa, said that only 400 people are currently registered as foreign agents. "Does anyone seriously think that only 400 people in the whole United States take foreign money for P.R. and lobbying work?"
Michael Horowitz, inspector general at the Department of Justice, testified that Congress needs to put "some teeth into the statute," noting there are no penalties for failing to register as a foreign agent.
Sen. Dianne Feinstein of California, the ranking Democrat on the panel, said she doesn't "know a time when the United States feels more invaded," referring to the findings that 21 states had their elections systems "pierced in this last election, we believe by Russia," and calling the Russian campaign last year an "interference with our sovereignty."
Grassley and Feinstein had hoped to have President Trump's former campaign chairman Paul Manafort testify, along with Donald Trump Jr., the president's eldest son.
Both men, along with Trump's son-in-law and top adviser, Jared Kushner, were present at a meeting at Trump Tower in June 2016 where they met with a Russian lawyer and two other Russian-Americans — with the understanding established beforehand that the lawyer, Natalia Veselnitskaya, was bringing damaging information about Hillary Clinton offered by the Russian government in order to help Donald Trump's presidential campaign.
Manafort retroactively registered under FARA in June for political consulting work he did for a Russia-aligned political party in Ukraine. The committee had planned to subpoena Manafort in an effort to bring him before the committee. But Tuesday night, the committee withdrew its subpoena, after Manafort agreed to provide documents to the panel. Grassley said the committee continues negotiations for a future transcribed interview.
Republicans meanwhile tried to turn attention to others who have failed to register under FARA, pointing to Hillary Clinton's adviser Sidney Blumenthal.
On Thursday, the panel will hear from William Browder, a businessman with financial dealings in Russia who advocated for passage of the Magnitsky Act.