A mystery woman posed as a senior Republican's wife to infiltrate high-level government talks on Obamacare and secretly record the conversation.
Donald Trump's inner circle has been desperately trying to uncover the identity of the intruder, who tricked her way into a meeting on national security at the private GOP retreat in Philadelphia.
She allegedly managed to slip through a heavy Secret Service presence, including metal detector checks, to enter one of the most secure buildings in the country.
The talks were attended by the President, Vice President Mike Pence, House Speaker Paul D. Ryan and other senior Republican members of Congress.
House GOP Conference Chairwoman Cathy McMorris Rodgers on Tuesday said she knew the identity of the woman who impersonated a congressman's wife to gain access to the talks, The Hill reports.
Republican Representative Carols Curbelo told the publication it was "concerning" that someone had managed to trespass at an event attended by the President and Vice President.
The woman emailed her recordings to news outlets including The Washington Post, exposing disagreements within the party on how to repeal and replace Barack Obama's Affordable Care Act.
They are deeply embarrassing for the Republicans and Mr Trump, who have insisted they have a clear plan for a better system to replace the former president's landmark healthcare scheme.
The issue is a complex one for the new administration, as there would be a public outcry if it were to take away health insurance from the tens of millions who have obtained it under the program.
Congressional Institute President Mark Strand emailed members of Congress over the weekend to explain that the woman had "infiltrated" the retreat with counterfeit credentials last Thursday between 7.30am and 6.30pm and "misrepresented herself on multiple occasions to retreat organisers as the spouse of an elected official".
She reportedly spent hours wandering the groups before she was escorted off the premises at 6.30pm.
The trip to Philadelphia for the Congress of Tomorrow Republican Member Retreat was Mr Trump's maiden journey as President.
The annual three-day policy retreat marked an opportunity for America's most senior politicians to put together their legislative agenda for 2017.
The investigation into the intruder is ongoing.