Just hours after dozens of House Republicans stormed a closed-door deposition in a secure area and disrupted Democrats' impeachment inquiry, House Oversight Committee ranking member Jim Jordan kept the pressure on Democrats by pushing for more transparency -- including public testimony from the whistleblower at the center of the probe.

In an initial letter to House Intelligence Committee Chairman Adam Schiff on Wednesday, Jordan -- joined by House Intelligence Committee ranking member Devin Nunes and Foreign Affairs Committee ranking member Michael McCaul -- called for the whistleblower to come out of hiding, so that his or her "sources and credibility" can be "fully assessed."

The committee chairs noted that Schiff had previously promised that the whistleblower would provide "unfiltered" testimony "very soon" concerning an Aug. 12 complaint.

But, the Republicans charged, Schiff abruptly "reversed course" after reports of the whistleblower's potential political bias emerged, along with evidence that Democratic congressional committee staff had spoken to the whistleblower before the complaint was filed.

READ THE REPUBLICANS' LETTER TO SCHIFF

The Republicans asserted that evidence has also emerged that "contradicts" the claims in the whistleblower's initial complaint, including that the Ukrainian president has said he felt no "pressure" during a July call with President Trump to investigate 2020 Dem front-runner Joe Biden, his son Hunter and Biden business interests in Ukraine.

Multiple apparent inconsistencies in the whistleblower's complaint, including the whistleblower's erroneous claim that Trump had asked Ukrainians to hand over a server, have previously prompted Republicans to demand more information on the person's sources.

The lawmakers further demanded testimony from any sources the whistleblower relied upon to draft the complaint, which contained only secondhand information.

The Republicans emphasized that they lack co-equal subpoena power with majority Democrats -- a key one-sided limitation that the White House has cited in explaining why it will not cooperate with the Democrats' probe.

GOP STORMS THE SCIF

House Republican Whip Steve Scalise, R-La., claimed that Schiff "fled with the testifying witness" when roughly 50 Republicans, including several not on one of those three committees, went "face-to-face and demand access to ongoing impeachment proceedings."

Some Republicans asked to be arrested by Capitol police officers, Fox News has learned, hoping that it would help them make their case that Democrats are abusing the impeachment process.

The whistleblower has acknowledged to the Intelligence Community Inspector General (ICIG) that bias against Trump might be alleged against him or her for a third, previously unreported reason, sources familiar with the ICIG investigation told Fox News on Wednesday.

Fox News has previously reported the whistleblower is a registered Democrat and had a prior work history with a senior Democrat. Though Fox News has learned that an additional element of possible bias was identified by the whistleblower, its nature remains unclear.

Separately, Fox News has obtained a letter from Jordan to Acting Assistant Secretary of State Philip Reeker, who was slated to come to Capitol Hill on Wednesday for a deposition. Fox News reported Monday night that the deposition was rescheduled for Saturday, when the House would not be in session, ostensibly because House members did not want to conduct interviews during the ceremony Thursday in which the late Rep. Elijah Cummings, D-Md., who'd headed the House Oversight committee, will lie in state at the Capitol before his funeral in Baltimore on Friday.

In the letter, Jordan asserted that many members won't be able to attend the unusual Saturday session, and pushed Reeker to explain why the deposition was moved. Jordan asked Reeker “to testify on a business day to allow robust member attendance and participation," and suggested Schiff was hoping to continue to shroud the impeachment proceedings in unhealthy secrecy.

Jordan said he regrettably had to ask Reeker directly for the information, because he had he has "no confidence" that Schiff, as the leader of the impeachment inquiry, is "operating fairly or in good faith."

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Jordan also asked Reeker about his "announced participation in a panel discussion sponsored by the Atlantic Council," which in 2018 received between $100,000 and $249,000 from Burisma -- the Ukraine natural gas company where Hunter Biden, Joe Biden's son, obtained a lucrative role despite not having any relevant expertise. The Atlantic Council, Jordan noted, recently removed Reeker's name as a panelist at the event.

Specifically, Jordan asked Reeker why he was removed as a panelist, and who proposed rescheduling his testimony -- and why they picked a Saturday.

Fox News' Chad Pergram and Catherine Herridge contributed to this report.