In a tense and dramatic exchange in the moments following Tuesday's Democratic debate, Elizabeth Warren accused Bernie Sanders of calling her a liar on national television.
Sanders replied that it was Warren who called him a liar and said they shouldn't talk about it at that time.
When the debate on CNN / Des Moines Register ended, the studio audience and viewers watched Warren walk over to Sanders and not shake his outstretched hand. The two senators seemed to have a brief, heated exchange before Sanders seemed to throw his hands up, turn around and leave. The video of the exchange aired without audio.
But the sound of the moment was captured by CNN's microphones and found on Wednesday.
"I think you called me a liar on national TV," Warren can be heard saying.
"What?" Sanders replied.
"I think you called me a liar on national TV," she repeated.
"You know, let's not do that now. If you want to have this discussion, we'll have this discussion," said Sanders, to whom Warren replied, "Anytime."
"You called me a liar," continued Sanders. "You told me – okay, let's not do this now."
After the exchange, Democratic candidate Tom Steyer, who was behind the two senators, can be heard saying, "I don't want to be in the middle. I just want to say hello, Bernie."
A Sanders campaign spokesman declined to comment on the audio. A Warren campaign spokesman did not respond to a request for comment.
The tense interaction between Sanders and Warren ended a 48-hour period in which the two progressive leaders on the presidential front, who spent most of a year-long campaign without any public signs of discord, were suddenly put at odds.
On Monday, Warren said Sanders told her during a private 2018 meeting that a woman could not win the presidency. On a CNN History published the same day, four sources said Sanders told Warren at the meeting that a woman could not win.
Sanders repeatedly denied the comment while Warren stood by saying yes – and that she disagreed with his assessment.
The brief post-debate discussion between Warren and Sanders was even more impressive because it occurred during a routine round of play between rivals, while crowd applause still echoed inside the Sheslow Auditorium at Drake University in Des Moines.
"Joe, good job," said Warren, reaching out to former Vice President Joe Biden. "Good to see you."
"Good job, Pete (Buttigieg)," said Sanders. "Good job, Amy (Klobuchar)."
So Warren came face to face with Sanders and confronted him, piercing the non-aggression pact he had last year.
It was remarkable that, before the debate, the two senators shook hands when they reached the stage. When they left, they didn't.
The conversation was not captured in the main audio feed of the candidates' podiums. Following the debate, CNN took stock of the audio equipment used and found two backup recordings of the microphones Sanders and Warren were using.
CNN synchronized the audio recordings with the images broadcast live on Tuesday night.
The conversation took place on the stage of the debate, in public view, and took place before the removal of Sanders and Warren's plug-in microphones.
During Tuesday's debate, Sanders and Warren doubled their different accounts at the 2018 meeting.
Pressured by the moderators, Warren called Sanders a "friend" and insisted that she was not there "to try to fight Bernie" before addressing the broader issue of women presidential candidates.
Sanders, who had said he "didn't want to waste too much time on this because (it's a fight between them) what Donald Trump and maybe some of the media want," vehemently denied questioning whether a woman could win the presidency.
"Anyone who knows me knows that it is incomprehensible that I think that a woman cannot be president of the United States," he said. "Go to YouTube today. They've had a video of me for 30 years talking about how a woman could become president of the United States."