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Sanders clashes with Warren – and the moderators – on sexism charge at heated Iowa debate
The final Democratic presidential debate before the pivotal Feb. 3 Iowa caucuses turned tense Tuesday night, as Bernie Sanders and Elizabeth Warren sparred over the disputed reports that Sanders had privately told Warren in December 2018 that a woman could not realistically become president.

“Well, as a matter of fact, I didn’t say it," Sanders insisted, after one of the CNN debate's moderators asserted the conversation had occurred. Later, when asked whether he was unequivocally denying that the conversation took place, he said, "That is correct."  A debate moderator then immediately and matter-of-factly asked Warren, "What did you think when Senator Sanders told you a woman could not win the election?"

That prompted laughter in the debate hall at Drake University in Des Moines, and a bewildered chuckle from Sanders. Some commentators have suggested the CNN report of Warren and Sanders' alleged 2018 conversation, which cited sources who were not present for Sanders' alleged remarks, was a leak from the Warren campaign intended to blunt Sanders' surge in recent polls.

The Sanders-Warren clash smashed the more than yearlong non-aggression pact between the two candidates and was just one of several flashpoints between the two that emerged during the debate. As the event concluded, Warren appeared to ignore Sanders' invitation for a handshake.

Sanders had a different focus early in the debate, as he challenged former Vice President Joe Biden's initial support for the Iraq war, which he called "the worst foreign policy blunder in the modern history of this country." Click here for more on our top story.

Other key Iowa debate developments:

- Winners and losers from the Iowa Democratic debate
- Bret Baier breaks down debate moments
- Warren-Sanders clash ‘very dispiriting,’ Dems' debate like 'cold oatmeal,' CNN’s Van Jones says
- 2020 Dems excluded from debate turn to commercial breaks

Ted Cruz floats idea of 'witness reciprocity' during Trump impeachment trial
Sen. Ted Cruz, R-Texas and a member of the Senate Judiciary Committee, pitched the idea of “witness reciprocity” on Tuesday during a meeting with Senate Majority Leader Mitch McConnell and other GOP leaders who convened to discuss strategy for the upcoming impeachment trial that will decide if President Trump is removed from office, Fox News has confirmed.

The idea would mean if Democrats call a witness, such as Trump’s former National Security Adviser John Bolton, Republicans would, in turn, be allowed to call a witness. Likely candidates to be subpoenaed by the GOP include former Vice President Joe Biden, his son Hunter Biden, House Intelligence Committee Chairman Adam Schiff and the unidentified whistleblower who reported a July phone call between President Trump and the leader of Ukraine.

The debate over possible impeachment witnesses comes as the Democrat-controlled House prepares for an imminent vote on advancing articles of impeachment to the Senate. Click here for more.

California attorney Michael Avenatti leaves a courthouse in New York following a hearing. Avenatti was arrested Tuesday by IRS agents for alleged violations of his pre-trial release. (AP Photo/Seth Wenig, File)

Avenatti arrested by IRS agents during California Bar Association hearing
California attorney Michael Avenatti was arrested by IRS agents Tuesday evening during a break in a disciplinary hearing in Los Angeles over allegations that the high-profile lawyer scammed a client out of $840,000.

The arrest occurred outside the State Bar Court, where the State Bar of California has initiated proceedings against him. Avenatti is accused of fraud, cheating on his taxes and lying to investigators as federal prosecutors allege that he embezzled funds from clients. The former attorney for porn star Stormy Daniels has pleaded not guilty to all the charges.

Thom Mrozek, a spokesman for the U.S. Attorney's Office in Los Angeles, told Fox News that Avenatti was arrested on suspicion of violating his pre-trial release. Click here for more.

Philippines volcano spews lava half-mile high, threatens to erupt again as flights grounded.
Red Sox and manager Alex Cora part ways after MLB sign-stealing investigation.
'Jeopardy!' just crowned this champ the 'Greatest of All Time.'

Michael Bloomberg is investing in getting rid of President Trump.
Four industries that will benefit most from 'phase one' US-China trade deal.
Scotch whisky industry trying to keep Trump tariffs from going higher.
#TheFlashback: CLICK HERE to find out what happened on "This Day in History."

Sean Hannity says Democrats have "every reason to be worried" about the 2020 presidential election and that they are in for an Election Day "shock" once again in Trump's favor.

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Fox News First is compiled by Fox News' Bryan Robinson. Thank you for making us your first choice in the morning! Enjoy your day! We'll see you in your inbox first thing Thursday morning.