CHICAGO (CBS) — President Donald Trump fired acting Attorney General Sally Yates on Monday, after she ordered Justice Department lawyers not to defend his travel ban in court.

The president replaced Yates with Dana Boente, U.S. Attorney for the Eastern District of Virginia, who was sworn in Monday night, and immediately directed the Justice Department to defend Trump’s executive order on immigration and refugees. Trump has said Boente will serve as acting attorney general until U.S. Sen. Jeff Sessions is confirmed as the next U.S. Attorney General.

The order, signed Friday, imposed a 90-day ban on travel to the U.S. by citizens of Iraq, Syria, Iran, Sudan, Libya, Somalia, and Yemen. The order also bars any refugees from entering the country for 120 days.

The ban also originally blocked legal permanent residents – green card holders – from the nations named in the president’s order from entering the U.S., but the Trump administration backtracked on Sunday amid growing outrage, and said green card holders would be admitted.

Yates’ ouster comes as protests continue at airports across the country, voicing opposition to the travel ban.

Critics of the president’s executive order were expected to rally at O’Hare International Airport and other major airports across the country Tuesday morning, the fourth consecutive day of protests.

While Trump has said his order is about national security, others have questioned its legality.

Scores of attorneys have been setting up shop at O’Hare since Saturday, offering free legal help to travelers affected by the president’s order. At least 18 people were detained on Saturday before they were released, after a federal judge in New York intervened, issuing a temporary order prohibiting the federal government from deporting people subject to the travel ban.

No travelers have been detained since then, although dozens have been questioned extensively as part of a “secondary inspection” process before they have been allowed to go on their way.

“We’re tracking two Jordanian nationals who were coming on tourist visas. One appears to have been sent back,” attorney Heather Donnell said.

Approximately 400 attorneys have signed up to volunteer their time to help people affected by the ban.

“For now we’re just trying to be here, trying to be a point of contact, and investigating when people are being held back, subject to the executive order,” attorney Rachel Olchowka said.

Monday morning, Jayshree Patel returned from a vacation in India, and she said Trump’s travel ban is a hot topic overseas.

“There is a big buzz about Trump leading this and taking it to the next level. I think it’s [the buzz is] all for good, I guess,” she said.

Meantime, U.S. Senate Minority Leader Chuck Schumer and other Senate Democrats have announced plans to introduce legislation that would overturn Trump’s travel ban.

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