(CNN) The House Ethics Committee released updates on their investigations into four lawmakers on Thursday, including a high-profile freshman Democratic lawmaker and a Republican lawmaker who they revealed is under investigation by the Department of Justice.

Florida Democratic Rep. Alcee Hastings faces a probe into an alleged relationship with a staffer, while Michigan Reps. Bill Huizenga, a Republican, Rashida Tlaib, a Democrat, and Rep. Ross Spano, a Republican from Florida, face varying alleged campaign finance violations. The committee has been investigating these lawmakers and announced on Thursday that it was extending its investigations into each of them.

The committee noted "that the mere fact" of assessing each case "does not itself indicate that any violation has occurred."

Here are the details on the ongoing investigations:

Rep. Rashida Tlaib

Tlaib, a Michigan Democrat, faces allegations that she used campaign funds for personal use and the Office of Congressional Ethics has so far found "substantial reason" to believe the allegations are true.

According to the OCE report , the office found "that there is substantial reason to believe that Rep. Tlaib converted campaign funds from Rashida Tlaib for Congress to personal use or Rep. Tlaib's campaign committee expended funds that were not attributable to bona fide campaign or political purposes."

The office recommended that the committee subpoena Tlaib and three of her campaign staffers who did not cooperate.

Tlaib said in a lengthy statement to CNN that the matter involved a "salary I earned under a Federal Election Commission (FEC) rule that allows non-incumbent candidates to receive a salary from their campaign to make up for lost income while running for office."

After leaving her job as an attorney to campaign full-time and "consulting with my campaign leadership and attorney, the campaign ultimately decided to pay me a salary as permitted under FEC regulations to ensure I could focus on winning the election," Tlaib said, asserting that "I was paid less than I was entitled to receive under FEC regulations."

"I have cooperated fully and forthrightly, providing hundreds of pages of documents, emails, and text messages to the Office of Congressional Ethics and the Ethics Committee, and making my staff available to the Committee for interviews," she said, adding that "I hope my experience will clear more room for people like me to run for office by availing themselves of FEC innovations that level the playing field, like paying a non-incumbent candidate salary or covering childcare expenses with campaign funds, so that financial privilege is not a prerequisite to participate in our democracy."

Rep. Ross Spano

Ethics committee leadership also agreed to extend its review of Spano, a Florida Republican, because it is now with the Department of Justice.

"The Department of Justice has asked the Committee to defer consideration of this matter and the Committee, following precedent, unanimously voted to defer consideration of this matter at this time," the committee announced Thursday.

According to the Office of Congressional Ethics report , Spano "may have received improper loans to support his election to the House of Representatives" that "may have exceeded federal campaign contribution limits." The report did not include findings.

Spano said in a statement Wednesday that he plans "to cooperate fully with the Justice Department on this matter."

"As I've said before, we acknowledged that mistakes were made with respect to the campaign loans, but those mistakes were completely inadvertent and unintentional. We were the ones who self-reported this to the FEC," he continued. "We are confident that upon review, the Justice Department will see it that way, too."

Spano also linked the investigation to the ongoing impeachment inquiry into President Donald Trump, adding, "I continue to have doubts about the timing and motive behind this inquiry, as the impeachment proceedings this week have shown me how far the left will go to destroy their opponents."

Rep. Bill Huizenga

In September, ethics committee leadership decided "to extend the Committee's review" of a case involving Huizenga, a Michigan Republican, that was referred by the Office of Congressional Ethics in August, with plans to "gather additional information necessary to complete its review."

The office concluded in its report that "there is substantial reason to believe that Rep. Huizenga accepted contributions form congressional staffers" and that his campaign committee "reported disbursements that were not for legitimate and verifiable campaign expenditures."

The OCE wrote that it reviewed "campaign-related trips Rep. Huizenga, members of his staff, and their families took from 2015 to 2018," including several trips to Disney World.

Huizenga's communications director Brian Patrick slammed the report as a politicized attack.

"After months of investigation, Nancy Pelosi's foot soldiers produced a partisan report that continues the false narrative created by the Michigan Democratic Party," Patrick said in a statement. "This matter has already been resolved and dismissed by the Federal Election Commission. We have fully cooperated in the investigation and eagerly await a timely resolution."

Rep. Alcee Hastings

The committee announced on Thursday that it had been investigating "public allegations arising out of Representative Alcee Hastings' personal relationship with an individual employed in his congressional office" since May.

Hastings, a Florida Democrat, did not respond to CNN's multiple requests for comment. He told the South Florida Sun Sentinel in a statement that he has "cooperated with the committee," and that, "As they continue to conduct their work, I stand ready to fully cooperate with their inquiry."

Hastings appeared to confirm the relationship when he told the Palm Beach Post in April that "he remained in a relationship with a member of his congressional staff," but said that "he is unconcerned with the appearance of impropriety generated by his relationship."