Demonstrators gather at Dulles International Airport on Jan. 29 to protest President Trump’s executive order barring citizens of seven Muslim-majority countries from entering the United States. (Thomas Watkins/AFP/Getty Images)

Problems entering the United States eased Monday for some international travelers after a weekend of confusion about a travel ban President Trump imposed, but members of Congress said border protection and administration officials still had not answered critical questions.

After Rep. Robert C. “Bobby” Scott (D-Va.) made a late-night visit to Dulles International Airport on Sunday — and was denied an audience with Customs and Border Protection officials — he received a short written response, his staff said Monday.

“There are no people in CPB custody at Dulles per the executive order,” read an email he received after 11 p.m. Sunday from a congressional affairs official at the agency.

The email did not address other specific questions from Scott, including how many people in all have been detained and whether any detainees have been removed from the airport — or from the jurisdiction of the federal court in the Eastern District of Virginia, which had ruled Saturday on a case stemming from Trump’s order.

U.S. District Court Judge Leonie Brinkema issued a temporary restraining order Saturday blocking green-card holders arriving at Dulles from being removed from the country. The order also said they any green card holder detained at Dulles should have access to a lawyer.

(Karen Attiah/The Washington Post)

Lawyers complained Sunday that they weren’t being given access to potential detainees. There also were mixed messages and confusion from the Trump administration about whether the order applied to green-card holders.

Sen. Tim Kaine (D-Va.) said he confirmed Monday that permanent legal residents — green-card holders — are subject to the executive order.

Kaine said he received the clarification during a phone call Monday with officials from U.S. Customs and Border Protection. He later met with volunteer lawyers at Dulles International Airport.

Kaine said he was told that, unlike with others traveling from seven Muslim-majority countries covered under the Trump’s travel ban, green-card holders are allowed to board planes to the United States. Once they arrive, they face questioning. But it is expected, at the discretion of border authorities, that they will be granted a waiver that allows them to enter the country, he said.

“The fact that they’re still saying the order applies to them but then there’s a waiver of it, it’s still a little bit odd, so I’m confused about that still, so more work to do,” he said during a tour of a library in downtown Roanoke.

Kaine said the same procedure applies to people given special immigrant status, such as translators who worked with the U.S. military.

At Dulles on Monday, dozens of demonstrators were back to welcome international visitors, and a contingent of lawyers was on hand to monitor any problems.

Hayley Tamburello said an Iranian citizen whose case she was tracking arrived on a flight from Dubai. He is a permanent legal resident and made it through security in a couple of hours. Other than some missing luggage, things went smoothly, Tamburello said.

But she said it was difficult to know whether other travelers were being held up by Customs and Border Protection authorities and whether others were being held elsewhere.

“It’s a lot easier for them to say they’re not detaining anyone if they’re not physically here,” Tamburello said.

Lawyers for two Yemeni brothers who were detained at Dulles on Saturday shortly after Trump issued his order said in a legal filing Monday that their clients had been lied to by U.S. authorities and coerced to sign forms they didn’t understand before being put on a return flight to Ethiopia.

The brothers, who are 19 and 21 years old, are now in “limbo” at Addis Ababa Bole International Airport and should be flown back to Dulles, so they can reunite with their father, a U.S. citizen, according to an amended complaint filed in the U.S. District Court for the Eastern District of Virginia.

“They were handcuffed. . .They were told if they didn’t sign a form. . .they would be put into official removal proceedings” and barred from the United States for five years, said Paul Hughes, a partner at the firm Mayer Brown who is among those working on the case.

The brothers, Tareq Aqel Mohammed Aziz and Ammar Aqel Mohammed Aziz, had been approved for legal permanent residence status in the United States, Hughes said, and do not want to return to Yemen because of the civil war there.

A spokesman for Customs and Border Control did not respond to a request for a comment.

At Dulles, Kaine greeted a woman holding a “Muslims Are Welcome” placard, and checked out a variety of other cheering demonstrators with signs, including one that declared “I’m from Sudan, don’t panic.” Sudan is one of the countries targeted in Trump’s temporary travel ban.

“I place my hope in these lawyers. I place my hope in Congress,” Kaine said.

Kaine said smaller communities in Virginia are among those being hit by the travel ban, pointing to scores of people at Virginia Tech who are being affected.

Kaine noted the case of a Syrian refu­gee family that moved to Blacksburg a year ago and has successfully become part of Virginia, a place where “Jeffersonian values and freedom of religion are personal.” The father got a construction job, and the crew pitched in money for soccer shoes for the family’s kids, Kaine said.

“We are a welcoming state, not a hard-hearted state,” Kaine said. The Trump order runs contrary to that spirit, he said. “This is a religious test, pure and simple.”

Also Monday, Sen. Bill Nelson (D-Fla.) sent a letter to Elaine Chao, Trump’s nominee for transportation secretary, asking several questions about the order. Chao is scheduled for a confirmation vote Tuesday.

Nelson asked Chao whether she agrees with the order and whether she was consulted before it was issued, and, if not, whether the Transportation Department should be consulted on “any further travel restrictions to minimize passenger and industry disruption.” Nelson also asked, given the “general confusion caused by the lack of clear communication from the administration in implementing” the president’s order, whether airports should be reimbursed by the federal government.

Nelson said many passengers caught in the “last-minute” travel ban “suffered substantial losses — including ticket cancellation penalties,” and he asked Chao if DOT should develop policies on such fees for other last-minute government actions to come.

Throughout the day Sunday, lawyers sought information about whether green-card holders or other international travelers were being detained at Dulles, but said they received no official information until getting a late-night comment Sunday similar to the one Scott received.

Mirriam Seddiq, who has spent days working with other volunteer lawyers at Dulles, said she spoke directly with a customs official at the airport. “I asked him if anyone was being detained. He said, ‘No, my backroom’s clear. Our work is done here,’ ” she recalled.

Seddiq said immigration lawyers and border authorities often have a different understanding of the word “detain,” making government comments hard to parse.

“Their idea of ‘detained’ is somebody put in handcuffs” and potentially carted away, she said. “Our idea of ‘detained’ is somebody who is back there who is being interrogated and who’s not able to come out in a timely fashion.”

Seddiq said immigration lawyers are working to figure out whether anyone was transferred from Dulles, and whether travelers faced difficulties Monday. Lawyers also are trying to document the cases of people barred from flying to the United States and are considering further legal action.