Speaker John Boehner’s top immigration aide was at the center of a heated dispute between the speaker and Rep. Louie Gohmert (R-TX) at a closed-door conference meeting Tuesday, according to several people who witnessed the altercation.

Gohmert, speaking to the audience of Republican lawmakers during an open mic portion of the meeting, asked Boehner whether Becky Tallent, the speaker’s immigration aide who has drawn fire from immigration hawks, had authored the House GOP bill to address the border crisis scheduled to be voted on Thursday.

Boehner rose from his chair and told Gohmert to knock it off, that he was “sick” of him bringing up Tallent. According to one member present, Boehner was visibly angry, “erupting” out of his chair to address Gohmert.

As Boehner turned back around, Gohmert stood silently for a moment before asking, “So then why did you hire her?”

Without getting back up to the microphone, his voice raised, Boehner retorted, “because she’s well-qualified on immigration!”

Tallent was in the room during the Boehner-Gohmert dust-up, and several Republicans said the episode was painfully awkward to watch.

One Republican at the meeting called Gohmert’s conduct “disturbing” and “deranged” and said “Boehner did exactly the right thing, and I only wish he’d expelled Gohmert from the room.”

Boehner hired Tallent in December from the Bipartisan Policy Center. She had previously been deeply involved in efforts to pass immigration reform in 2007-2008 as Sen. John McCain’s (R-AZ) chief of staff, and her hiring quickly became a flash point in the immigration debate.

Top proponents of immigration reform hailed her hiring, while immigration hawks called it a worrying sign. In the time since, her work on the issue has been closely scrutinized.

“There are jobs that American workers will not do,” Tallent said during a C-SPAN segment in 2013. She also advocated for the Senate Gang of Eight bill.

During consideration of the border crisis bill, there has been considerable private speculation from critics of the legislation that it was primarily authored by Tallent.

Michael Steel, a spokesman for Boehner, downplayed Tallent’s role in crafting the bill, saying, “the House border working group, led by Rep. Kay Granger (R-TX) and the House Appropriations Committee, chaired by Hal Rogers (R-KY), developed the border crisis bill.”