Members of Maine’s congressional delegation said Thursday that a whistleblower complaint released Thursday heightened their concerns about President Trump’s request that Ukrainian officials investigate one of his top political rivals.

“After reading the abridged summary of the Ukraine phone call released (Wednesday) by the White House and the whistleblower complaint, it is clear to me that this is a matter of serious concern,” Sen. Angus King, an independent, said in a statement. “That is why the House must conduct a thorough and transparent inquiry to collect all evidence, free of interference from any of the administration officials who may have been involved – including Attorney General Bill Barr, who should recuse himself from this process.”

The nine-page complaint – dated Aug. 12 and addressed to the chairmen of the House and Senate intelligence committees – alleges that the president “is using the power of his office to solicit interference from a foreign country in the 2020 U.S. election.”

While the complaint mirrors some of the details provided by the White House on the July 25 conversation between Trump and Ukraine’s president, it also contained new details that only intensified some Democrats’ calls for impeachment.

For instance, the whistleblower alleges that White House lawyers directed staff to remove the electronic transcripts of the call from the normal computer system and, instead, loaded them into a separate system used for classified information. Additionally, the complaint outlines how the Trump administration suspended “security assistance” to Ukraine in the days prior to Trump asking the Ukrainian president for help investigating Biden.

Rep. Chellie Pingree, D-1st District, already has come out in support of the impeachment process, and said the whistleblower complaint only deepened her concerns about the president’s behavior.

“I find it so discouraging reading about the depths the president would sink to and not seem to understand it is illegal and inappropriate to go to a foreign government for help investigating a political opponent or Democrats,” Pingree said. “It’s unpatriotic.”

Thursday was another tumultuous day on Capitol Hill as the whistleblower complaint and House Democrats’ impeachment inquiry continued to dominate news coverage and overshadow any other work.

On Thursday morning, acting Director of National Intelligence Joseph Maguire spent several hours fielding pointed questions from the House Intelligence Committee during a meeting that was conducted in open session. Hours later, Maguire appeared before members of the Senate Intelligence Committee during a closed session, as did the inspector general of the intelligence agencies, Michael Atkinson, during a separate briefing.

Both King and Maine Republican Sen. Susan Collins serve on the Senate Intelligence Committee and participated in the closed-door briefings with Maguire and Atkinson.

Collins told reporters afterward that “it was a worthwhile discussion” with both men. She also told a Bloomberg reporter that it was “a gross mischaracterization of whistleblowers” for Trump to refer to those who provided information to the whistleblower as spies and said she believes the inspector general can continue to investigate the case.

“There are obviously a lot of questions, and I personally believe that the (inspector general) does have the legal authority to proceed under the law, to investigate,” Collins said after the closed-door committee briefing, according to information provided by her office. “There is some ambiguity, and I recognize that the (Justice Department’s) Office of Legal Counsel has reached a different conclusion, but I believe that the IG’s legal analysis is correct.”

King did not comment on the closed-door session.

After declining to weigh in on the impeachment question for months, King said this week that the House “had no choice but to make use of its only remaining option: the opening of an impeachment inquiry.” King added, however, that he would wait to see the results of the House impeachment inquiry before coming to any conclusions.

“As a member of the Senate, I am prepared to review all of the information the House is able to collect in its process, and will do my best to judge the evidence in a way that fulfills my oath to ‘support and defend the Constitution against all enemies, foreign and domestic,'” said King, an independent who caucuses with the Democrats.

Pingree said she was unable to watch Maguire’s appearance before the House Intelligence Committee on Thursday morning because she was involved in a committee hearing on forestry issues. But she strongly supports robust committee investigations into the issue.

“I think it’s really critical that our committees call witnesses – (Rudy) Giuliani, (Attorney General) William Barr and people from the State Department – and investigate what we saw in writing from what seems to be a very credible whistleblower.”

Pingree’s House colleague, Rep. Jared Golden, D-2nd District, has stopped short of supporting an impeachment inquiry until more facts are known. A Golden spokesman did not respond to a request for a comment on Thursday on the release of the whistleblower complaint, although Golden said Tuesday that Trump’s “statements and reported actions raise novel and serious questions about his commitment to putting the good of the country before his own interests.”

Democrats acknowledge that the House impeachment inquiry carries significant political risk for their party and for the 2020 presidential elections. Two polls released Thursday highlight those risks but also suggest public support for the impeachment process may be growing in response to the revelations about Trump’s request that Ukrainian leaders help investigate one of his top potential opponents in 2020.

A Marist Poll conducted Wednesday night for NPR/PBS Newshour found that 49 percent of respondents supported the House starting an impeachment inquiry while 46 percent disapproved and 5 percent undecided. While Democrats and Republican respondents fell along predictable lines, only 44 percent of independents supported the impeachment proceedings compared to 50 percent opposed.

A Morning Consult poll, meanwhile, found respondents deadlocked at 43 percent on the question. But support for the House impeachment inquiry had grown 7 percent since last weekend while opposition had fallen 6 percent.