GEOFF BENNETT: Welcome to the "News Hour."

A typically ordinary Senate hearing on worldwide threats to the U.S. became contentious today following news of a major national security breach.

The editor in chief of "The Atlantic" revealed yesterday that he was accidentally put into a chat on the Signal messaging app with top U.S. officials as they discussed military strikes in Yemen.

Two of those officials testified in the Senate hearing today.

Our congressional correspondent, Lisa Desjardins, has our report.

SEN. MARK WARNER (D-VA): I can just say this.

If this was the case of a military officer or an intelligence officer and they had this kind of behavior, they would be fired.

LISA DESJARDINS: Democrats on the Senate Intelligence Committee today hammered CIA Director John Ratcliffe and director of national intelligence, Tulsi Gabbard, over the Signal chat security breach.

SEN. MARK WARNER: Director Ratcliffe, were you on the group chat?

JOHN RATCLIFFE, CIA Director: Senator, I was on a Signal messaging group.

SEN. MARK WARNER: So you were the John Ratcliffe on that chat?

JOHN RATCLIFFE: I was.

SEN. MARK WARNER: Thank you.

Thank you.

LISA DESJARDINS: Throughout the heated hearing, Ratcliffe and Gabbard stayed cool, confirming they do use the encrypted app for work purposes and stating it's allowed for high-level use.

Initially, both denied the chat contained classified information.

JOHN RATCLIFFE: To be clear, I haven't participated in any Signal group messaging that relates to any classified information at all.

SEN. RON WYDEN (D-OR): OK. Director Gabbard?

TULSI GABBARD, U.S. Director of National Intelligence: Senator, I have the same answer.

I have not participated in any Signal group chat or any other chat on another app that contained any classified information.

LISA DESJARDINS: In "The Atlantic"'s bombshell report, editor and chief Jeffrey Goldberg wrote the text chain disclosed -- quote -- "information about targets, weapons the U.S. would be deploying, and attack sequencing."

Asked about those specifics, Gabbard and Ratcliffe gave versions of the same nonanswer.

JOHN RATCLIFFE: I don't recall.

TULSI GABBARD: I don't recall giving that instruction.

JOHN RATCLIFFE: In that setting, I don't recall.

LISA DESJARDINS: With a few definitive moments.

SEN. MARK KELLY (D-AZ): The deliberation between principals in our national security apparatus about whether or not to strike another country, would you consider that to be classified information?

JOHN RATCLIFFE: Pre-decisional strike deliberation should be conducted through classified channels.

SEN. MICHAEL BENNET (D-CO): Is your testimony that it was appropriate that he was added to this Signal thread?

LISA DESJARDINS: Democrats say the chat posed an unacceptable national security risk.

SEN. MICHAEL BENNET: Did you know that the president's Middle East adviser was in Moscow on this thread while you were, as director of the CIA, participating in this thread?

Were you aware of that?

Are you aware of that today?

JOHN RATCLIFFE: I'm not aware of that today.

SEN. MICHAEL BENNET: This sloppiness, this incompetence, this disrespect for our intelligence agencies and the personnel who work for them is entirely unacceptable.

It's an embarrassment.

JOHN RATCLIFFE: Senator... SEN. MICHAEL BENNET: You need to do better.

LISA DESJARDINS: Later in the hearing, Gabbard and Ratcliffe seemed to say that nothing classified from their agencies was involved, but they couldn't speak for the Pentagon.

SEN. MARK WARNER: It's stunning to me.

And the idea, somehow, well, none of this was classified, but we can't talk about it here, you can't have it both ways.

SEN. TOM COTTON (R-AR): I think the witnesses' point is, they can't speak for every official in the government who has original classification authority.

LISA DESJARDINS: Most Republicans didn't ask about the leak.

A few said they would talk only behind closed doors.

SEN. MIKE ROUNDS (R-SD): I'm going to address it, but I'm going to address it in the closed session.

LISA DESJARDINS: Outside the hearing room, one Republican who stopped had little to say.

SEN. JOHN CORNYN (R-TX): I mean, you heard what I heard.

I don't really have anything to add to that.

I just think there's going to be -- have to be more investigation into the facts and circumstance.

LISA DESJARDINS: But at least one House Republican was critical with me earlier today.

REP. DON BACON (R-NE): China and Russia is clearly on these networks.

You are -- you put people's lives at risk when you do this.

So it's wrong.

There's no two -- there's no ambiguity here.

LISA DESJARDINS: Former Intelligence Chair and ranking Democrat Mark Warner went much further, particularly about Hegseth, who reportedly shared the most specifics.

SEN. MARK WARNER: For me, particularly, if Secretary Hegseth let this information out, he should resign.

LISA DESJARDINS: For his part, Hegseth has slammed the report, late yesterday saying it was flat wrong.

PETE HEGSETH, U.S. Defense Secretary: Nobody was texting war plans, and that's all I have to say about that.

DONALD TRUMP, President of the United States: We will look into it.

LISA DESJARDINS: President Trump, speaking today in the White House Cabinet Room, played down the breach... DONALD TRUMP: There was no classified information.

LISA DESJARDINS: ... and called on National Security Adviser Mike Waltz, whose account added Goldberg.

Waltz praised Trump, blasted the press, and offered no contrition.

All of this eclipsed a hearing that was supposed to focus on outside threats, like Iran, which Gabbard said is not building a nuclear weapon currently, but: TULSI GABBARD: Iran's enriched uranium stockpile is at its highest levels and is unprecedented for a state without nuclear weapons.

LISA DESJARDINS: ... and like cartels, named the top threat this year.

Independent Angus King of Maine noticed something not in the report.

SEN. ANGUS KING (I-ME): Has global climate change has been solved?

Why is that not in this report?

And who made the decision that it should not be in the report, when it's been in every one of the 11 prior reports?

LISA DESJARDINS: Dominating not just the hearing, but much of Capitol Hill today, was still the Signal chat.

MAN: It is absolutely unacceptable.

LISA DESJARDINS: With a dozen House Democrats who served in the military calling for an investigation, adding another question to the story.

How will Capitol Hill Republicans in charge handle this breach by their own?

For the "PBS News Hour," I'm Lisa Desjardins on Capitol Hill.

GEOFF BENNETT: And we asked each of the Republican senators on the Intelligence Committee to join us for an interview tonight, but none accepted our invitation.