Updated at 3:44 p.m. ET
The members of the Senate Intelligence Committee had one question they asked again and again Wednesday of the country's intelligence chiefs: Did President Trump want you to downplay investigations surrounding Russia?
And time and again, the intelligence officials declined to answer.
At the often contentious hearing, Virginia Democrat Mark Warner, the committee's vice chairman, was the first to press the question. He asked the director of national intelligence, Dan Coats, and the head of the National Security Agency, Adm. Mike Rogers, about media reports that Trump asked them to intervene in the Justice Department investigation of former national security adviser Michael Flynn, and the broader inquiry surrounding Russia.
Both answered in broad terms.
"In the three-plus years I have been director of the National Security Agency, to the best of my recollection, I have never been directed to do anything illegal, immoral, unethical or inappropriate," Rogers said. "I do not recall ever feeling pressured to do so."
Coats responded in a similar vein.
"In my time of service," Coats said, "I have never been pressured, I've never felt pressure to intervene or interfere, in any way, with shaping intelligence in a political way."
However, neither would discuss their conversations with Trump, and declined to say if he asked them to take any action regarding the investigations.
Warner, along with several other senators, kept pushing and ultimately expressed frustration with the intelligence chiefs.
There are "reports, that nobody has laid to rest here, that the president of the United States has intervened directly in an ongoing FBI investigation and we've got no answers from any of you," Warner said.
The verbal sparring became so intense that Committee Chairman Richard Burr, a North Carolina Republican, intervened at one point during a sharp exchange between California Democrat Kamala Harris and Deputy Attorney General Rod Rosenstein.
"The chair is going to exercise its right to allow the witnesses to answer the question, and committee is on notice to provide witnesses the courtesy, which has not been extended all the way across," Burr said.
Republican John McCain of Arizona took a softer approach, drawing chuckles when he asked Coats, "Do you want to tell us any more about the Russian involvement in our election that we don't already know from reading The Washington Post?"
Coats did not offer any details, but said, "Just because it's in The Washington Post doesn't mean it's declassified."
The hearing brought four senior intelligence and law enforcement officials before the committee on Wednesday. In addition to Coats, Rogers and Rosenstein, Acting FBI Director Andrew McCabe also testified.
The hearing was highly anticipated because stories about the Russia investigation have emerged piecemeal, often based on anonymous sources. The intelligence chiefs are all key figures in the investigation, but have rarely spoken publicly, and not in one place, at one time, and under oath.
However, the hearing offered relatively little new information, and shortly after it ended at midday, it was overtaken by the release of a statement by James Comey, the former FBI director who was fired by Trump on May 9.
Comey is scheduled to testify before the committee on Thursday morning, and his prepared statement was posted on the committee's website. In the statement, Comey says Trump asked him for "loyalty" at a January dinner. Comey says the president also spoke to him about the investigation into former national security adviser Michael Flynn, and said, "I hope you can let this go."
The president has repeatedly called for an end to the various inquires swirling around his administration. But Democratic senators, in particular, want to know what he's told intelligence officials in private discussions.
Trump reportedly asked Coats and Rogers to state publicly that there was no collusion between Russia and the Trump campaign. Neither official has done so.
Citing these reports, Warner said in his opening statement:
"If any of this is true, it would be an appalling and improper use of our intelligence professionals — an act that could erode the public's confidence in our intelligence institutions. The (intelligence community) fiercely prides itself on its apolitical service to the country. Any attempt by the White House or even the president himself to exploit this community as a tool for political purposes is deeply, deeply troubling."
While Democrats have focused on possible collusion between Russia and the Trump campaign, Republicans have focused on leaks about the investigation.
The president has frequently railed against leaks, and a government contractor, Reality Winner, was charged Monday with leaking an NSA document that details Russian efforts to penetrate U.S. election systems.