Less than two weeks into the Trump administration, Senate Democrats have thrown down the gauntlet.

As protests rage over President Trump’s controversial executive order on immigration, members of the minority party announced Tuesday they would boycott confirmation hearings for two of Trump’s key cabinet nominees, Rep. Tom Price, R-Ga., for Secretary of Health and Human Services, and Steve Mnuchin for Secretary of the Treasury.

By not attending the hearings, Democrats are denying the committee a quorum and thus blocking it from advancing the nominations to the full Senate for a final confirmation vote.

Democrats, who have already raised concerns about Price’s active trading of stocks in health care companies that may have benefited from actions he took in Congress, seized on a Monday report in the Wall Street Journal that revealed the Georgia congressman was part of a small group of investors who had been offered discounted stock by a biotech firm.

The report contradicted Price’s previous claim to the Senate Health Committee that all of the initial investors purchased stocks at the lower price.

The Journal reports Price was one of 20 investors who were invited to invest in Innate Immunotherapeutics, an Australian firm whose largest shareholder, Rep. Chris Collins, R-N.Y., extended the offer to Price, who bought between $50,000 and $100,000 worth of stock at a 12 percent discount.

Democrats say they are halting Mnuchin’s confirmation over  the former hedge fund manager’s failure to disclose nearly $100 million of investments as well as what they say were abusive practices he oversaw as CEO of OneWest, a residential lender. They have highlighted aggressive foreclosures of homes, highlighting the case of a 90-year-old woman whose home was foreclosed on because of an underpayment of 27 cents.

"This is about getting answers to questions, plain and simple," Sen. Ron Wyden, D-Ore., says in a statement. "Ethics laws are not optional, and nominees do not have a right to treat disclosure like a shell game."

Republicans have responded with outrage. Just as Democrats accused the GOP of obstructing President Obama, most notably by refusing to hold a vote on Obama’s Supreme Court nominee for nearly a year, Congressional Republican leaders called the Democrats’ actions unprecedented.

“Some of this is just because they don’t like the president,” says Sen. Orrin Hatch, R-Utah, chair of the Senate Committee on Finance, which is responsible for advancing Mnuchin’s nomination to the full Senate.

Democrats, however, do not appear to show any signs of backing down, although they are not blocking nominees to other key posts, including Rick Perry to lead the Department of Energy and Rep. Ryan Zinke, R-Mont., to head the Department of the Interior.

“We’re going to hold Donald Trump accountable,” Senate Minority Leader Chuck Schumer told Spanish-language TV channel Univision, according to the Washington Post. “I think in our recent actions on immigration, on the Cabinet. We’re not letting him rush the Cabinet through.”