House Intelligence Committee Chairman Adam B. Schiff (D-Calif.) said Sunday that protecting the identity of the whistleblower who raised the alarm about President Trump’s communications with Ukraine is “our primary interest,” in a sign that House Democrats may not press the individual to testify before Congress.

Schiff made the statement in an interview on CBS News’s “Face the Nation.” He had said late last month that he expected his panel to hear from the whistleblower “very soon” pending a security clearance from acting director of national intelligence Joseph Maguire.

“You know, I think initially, before the president started threatening the whistleblower and threatening others — calling them traitors and spies and suggesting that, you know, we used to give the death penalty to traitors and spies and maybe we should think about that again — yes, we were interested in having the whistleblower come forward,” Schiff said.

Asked by host Margaret Brennan whether that meant his panel was not interested anymore, Schiff replied that “our primary interest right now is making sure that that person is protected — indeed, now [that] there’s more than one whistleblower, that they are protected.”

“Given that we already have the call record, we don’t need the whistleblower who wasn’t on the call to tell us what took place during the call,” Schiff said. “We have the best evidence of that.”

The complaint from the original whistleblower sparked House Democrats’ impeachment inquiry. An attorney for the individual said last week that “multiple” whistleblowers have come forward, and in recent weeks, Trump has escalated his attacks against them, alluding to the death penalty and suggesting that whoever gave the first whistleblower information was “close to a spy.”

The president also tweeted last week that the original whistleblower “should be exposed and questioned properly” — an argument he repeated during an appearance Saturday night on Fox News Channel.

“I think we have to find out who the whistleblower is that would give all this false information,” Trump told host Jeanine Pirro.

Trump’s allies have taken aim at the whistleblowers as well. Former U.S. attorney Joseph E. diGenova denounced the two anonymous individuals on Tuesday as “suicide bombers,” while Rep. Jim Jordan (R-Ohio) on Friday called for the first whistleblower’s unmasking.

“Why don’t we know who this whistleblower is?” Jordan told reporters at the Capitol. “They deserve protection, but … they’re not entitled to anonymity.”

Amid mounting safety concerns and fears that the person’s identity may be revealed, attorneys for the whistleblower have asked whether their client can submit testimony in writing rather than in person, according to a person familiar with the matter. The whistleblower’s attorneys have submitted the request to the House and Senate intelligence committees, the person added.

Schiff said Sunday that while Democrats continue to probe the actions of the president and his administration, they plan to take steps to protect the whistleblower’s identity.

“We do want to make sure that we identify other evidence that is pertinent to the withholding of the military support, the effort to cover this up by hiding this in a classified computer system,” Schiff said. “We want to make sure that we uncover the full details about the conditionality of either the military aid or that meeting with the Ukrainian president.”

Democrats are probing whether Trump’s decision to withhold nearly $400 million in military assistance from Ukraine was linked to his push for the government there to pursue political investigations that could bolster his reelection bid.

“It may not be necessary to take steps that might reveal the whistleblower’s identity to do that, and we’re going to make sure we protect that whistleblower,” he added.

Trump and other Republicans have argued that Democrats should hold public hearings rather than hear witness testimony behind closed doors. But Rep. Jim Himes (D-Conn.), who sits on the Intelligence Committee, argued Sunday that Democrats have several reasons for conducting closed-door depositions.

The “most important reason,” Himes said on ABC News’s “This Week,” is that “when you’re talking to ambassadors and other U.S. government officials who have regularly had access to classified information, you need to be able to talk about that information and then go back and say, ‘Hey, this conversation has to be redacted because it involves classified information.’ ”

The second reason, he said, is that lawmakers don’t want witnesses to be able to coordinate testimony.

“These are a group of people who have shown that they have no problem whatsoever lying, if they think it serves their interest,” Himes said. “And so you don’t want to give them the opportunity to look at what they are saying and therefore coordinate their stories.”

He added that “all transcripts will eventually be scrubbed for classified information and made available for the American public to see.”

Mike DeBonis contributed to this report.