CNN released audio of the exchange between Sens. Warren and Sanders at the end of the debate last night.
"I think you called me a liar on national TV," Warren can be heard saying.
"What?" Sanders responded.
"I think you called me a liar on national TV," she repeated.
"You know, let's not do it right now. If you want to have that discussion, we'll have that discussion," Sanders said, to which Warren replied, "Anytime."
"You called me a liar," Sanders continued. "You told me -- all right, let's not do it now."
Click the link for the video.