(CNN) — House Democrats plan to announce their articles of impeachment into President Donald Trump on Tuesday morning, pushing forward with their impeachment inquiry following a contentious hearing on Monday.

Leaving a meeting in House Speaker Nancy Pelosi’s office Monday evening, New York Rep. Eliot Engel, the chairman of the House Foreign Affairs Committee, told reporters there would be an announcement Tuesday morning to lay out the articles of impeachment, but wouldn’t say how many articles there are or detail their substance.

Engel said he expected the announcement would be made by the key Democratic chairs — Reps. Jerry Nadler of New York, Adam Schiff of California, Maxine Waters of California and Carolyn Maloney of New York.

“This is not a happy day,” Engel said, “but I think we are doing what we have to do.”

The announcement Tuesday will come one day after Nadler accused Trump of putting “himself before country” at a chaotic hearing kicking off a two-week sprint for Democrats likely to end in the third impeachment of a president in US history.

The hearing for Democratic and Republican staff attorneys to present cases for and against Trump’s impeachment saw the bitter partisan divide over the impeachment proceedings spilled into the open, with Republican lawmakers vocally protesting Nadler’s handling of the hearing and committee staffers even clashing during questioning.

Republicans erupted while Democratic Judiciary Committee staff counsel Barry Berke pressed GOP counsel Steve Castor on the Republican report and accused Republicans of inaccurately quoting a witness.

“He’s badgering the witness,” said GOP Rep. Jim Sensenbrenner of Wisconsin, trying to raise an objection to Berke’s questioning. When Nadler ruled he wasn’t raising a valid objection, Sensenbrenner said: “The chairman is not in order.”

The exchange was one of the many Republican objections that occurred Monday during a lengthy hearing where even the decision to recess prompted multiple party-line roll-call votes. As questioning of the staff attorneys began — which created an odd dynamic where one committee staffer was grilling another — the GOP protests intensified along with the volume of Nadler’s gavel banging down to stop the interruptions.

“Bang it harder — still doesn’t make it right,” said Rep. Doug Collins of Georgia, the top Republican on the House Judiciary Committee, in a shot at Nadler.

Democrats used Monday’s hearing opportunity to weave the hours of witness testimony to illustrate their narrative that the President abused his office.

“If he puts himself before the country in a manner that threatens our democracy, then our oath — our promise to the American people — requires us to come to the defense of the nation,” said Nadler, a Democrat.

Republicans also pointed to witness testimony to argue that Democrats didn’t have a case, charging they rushing to impeach Trump in order to beat him in the 2020 election.

“This may though become known as the focus-group impeachment,” Collins said. “Because we don’t have a crime, we don’t have anything we can actually pin and nobody understands really what the majority is trying to do except interfere and basically make sure they believe the President can’t win next year if he’s impeached.”

The objections to the hearing began as soon as Nadler started his opening statement, as a protester in the audience shouted down the Judiciary Committee chairman before being removed by US Capitol Police. Republicans on the committee then took up their own objections, demanding a hearing for the witnesses they want to hear from and accusing Nadler of “a steamroll” when he ignored their protests.

Republicans knocked House Intelligence Chairman Adam Schiff, a California Democrat who led the Intel panel’s impeachment inquiry, for not testifying before the Judiciary panel, with staff counsel Daniel Goldman appearing instead to discuss the committee’s report.

“We want Schiff in that chair, not you,” shouted Rep. Matt Gaetz, a Florida Republican.

Collins went after Goldman during his questioning over the committee’s subpoenas that revealed phone calls of Rep. Devin Nunes, the top Republican on the Intelligence Committee, and journalist John Solomon, whose opinion columns in The Hill attacked former US Ambassador Marie Yovanovitch. Goldman said that the committee didn’t subpoena either Nunes or Solomon, but that didn’t slow the Republican lawmakers’ criticisms.

“Somebody along the way just didn’t all of a sudden have an epiphany … that these numbers might match,” Collins said. “Who ordered it, was it you, or was it Chairman Schiff, and then why was it decided, except for nothing but smear purposes, to be included in the Schiff report?”

Monday’s hearing is likely to be just the opening act of a week’s worth of major Judiciary Committee activity on impeachment, as Democrats are expected to bring forward articles of impeachment that will be debated and voted on in the committee later this week.

Nadler declined to say what the committee’s next steps would be, saying he was “not prepared to say anything further about the schedule of the committee beyond today’s hearing.” But he concluded the hearing by declaring that Trump’s conduct was “clearly impeachable.”

“This committee will proceed accordingly,” he said.