Homeland Security Secretary John F. Kelly pauses while speaking at a news conference at the U.S. Customs and Border Protection headquarters. (Andrew Harnik/Associated Press)

Department of Homeland Security officials on Tuesday sought to defend their implementation of President Trump’s immigration order, as civil liberties attorneys said they were still pressing for more-thorough compliance with court rulings on the measure.

Homeland Security Secretary John F. Kelly said at a news conference Tuesday that department officials “are and will remain in compliance with judicial orders,” though attorneys for the American Civil Liberties Union said they were not fully convinced that was the case.

As of 7 p.m., for example, the administration had not yet provided a list of those detained to ACLU lawyers, despite a New York federal judge’s order that it do so, an ACLU lawyer there said. An ACLU lawyer in Los Angeles said the organization also has fielded reports that Customs and Border Protection agents are ­coercing holders of valid visas or green cards to voluntarily relinquish their documents, and a lawsuit in Virginia alleges similar conduct.

Senior Homeland Security officials on Tuesday sought to quell concerns about travelers being denied entry in violation of court orders, holding a news conference to discuss the details with reporters. Officials and civil rights lawyers said the situation on Tuesday was a far cry from over the weekend — when people with green cards and visas were being detained for hours on end, some of them ultimately flown out to other countries even as courts ordered that they should not be.

But civil liberties advocates said a lot of confusion remained over how the order — which temporarily bans refugees and citizens from seven Muslim-majority countries from coming to the United States — should be legally implemented. Also with the president’s firing of his acting attorney general over her refusal to defend the ban, they said they worried that the president was trying to run over normal checks on his authority.

In New York — where a federal judge ordered authorities nationwide to stop deporting or taking into custody those with valid immigrant and nonimmigrant visas — the ACLU said it was still pressing for a list of who had been detained. That list is important “to confirm that people have not been sent back in defiance of the court’s order, and whether people are still being detained or denied access to counsel,” said Lee Gelernt, deputy director of the ACLU Immigrants’ Rights Project.

“In the absence of the list, we would be left to simply take the unilateral assurances of the administration, which we will not do,” Gelernt said.

In Los Angeles, ACLU lawyers said they were still fielding reports of people who were being forced to endure hours-long processing, and sometimes coerced into signing away their legal rights to be in the United States. Jennie Pasquarella, a senior staff attorney at the ACLU of Southern California, said one visa holder from Syria who had permanent resident status in Saudi Arabia was pressured into giving up his rights to be here, though he left with documentation saying he could remain for 18 days.

She said people were still being held up — though not for nearly as long as when the order first took effect.

“It’s definitely felt like, at least through Sunday, they were ignoring the order, but it does seem like they have changed what they’re doing and not holding people in this prolonged manner,” Pasquarella said.

In some cases, the damage appears to already be done. Yemeni brothers Tareq and Ammar Aqel Mohammed Aziz, 21 and 19, for example, got into Dulles International Airport on Saturday morning. Their lawyers say they were then handcuffed and coerced, with no legal counsel present, into giving up the immigrant visas they had worked for years to secure. They were put on a plane to Addis Ababa, Ethi­o­pia, where they sat in the airport for three days without access to their passports, their lawyers said. On Tuesday, the brothers were sent to Djibouti, where for now they have been allowed to stay.

Sara Yarjani, 35, a master’s student at the California Institute for Human Science, said she was similarly pressured into signing away her visa at the Los Angeles airport when officials told her she could either do so and leave on her own, or be forcibly removed from the United States and face the prospect of a one-to-five-year ban.

Yarjani, an Iranian national whose parents live in Austria, said she spent 23 hours in custody Friday into Saturday, learning just before she was put on a plane of a judge’s order declaring that those like her should not be deported. She said she told Customs and Border Protection officers as much, and one simply responded “Wowzas” before ultimately ushering her on board.

“It was so terrible and heartbreaking,” Yajani said. “I’m still trying to find out what are the steps I can take.”

Attorneys general in four states have now moved to join the court battle over Trump’s immigration order. The most immediate front appears to be what happens when people try to board U.S.-bound planes overseas.

Immigrant rights advocates said this week that officials were preventing people from boarding those flights. Acting Customs and Border Protection commissioner Kevin McAleenan said that in the past 72 hours, 721 people with visas from the seven countries listed on the executive order had been denied permission at foreign airports to board flights headed to the United States, and asserted, “There were carriers that overinterpreted our guidance.”

The federal court orders constrain the actions of government officials after people have landed in the United States but seem to have little practical value to someone waiting to board a U.S.-bound plane overseas.

Immigrant rights attorneys said the government does not appear to be technically in violation of the court orders by advising airlines to turn away people before they have boarded planes heading to the United States, with the possible exception of people trying to fly to Boston’s Logan Airport.

Susan Church, one of the attorneys who brought the challenge there, said the judge’s order specifically requires Customs and Border Protection officers to tell the airlines that people traveling to Boston will not be deported or detained.

“The airlines, despite being notified, are claiming they don’t know about this order,” Church said Tuesday. “It’s really outrageous, and it’s violating the court order.”

U.S. officials conceded at Tuesday’s briefing that they had made mistakes and said that they would explore reports of people being coerced into signing away their documentation. Kelly said that a “small number” of travelers were being held up for extra processing but that none were detained. Officials with the Department of Homeland Security on Tuesday issued written guidance designed to give airlines and travelers a clearer understanding of new rules.

McAleenan also said that officials would soon allow 872 refugees into the country and that officers processed 1,060 waivers for green-card holders.

Officials struggled to explain why the rollout of the order over the weekend was so chaotic. One individual familiar with the process said that leaders from Customs and Border Protection and the other DHS agencies were briefed on the order’s details on Friday afternoon in a pair of urgent conference calls, including one after Trump signed it. A second individual said career operational staff and lawyers at Customs and Border Protection and Department of Homeland Security headquarters were not given an opportunity to review and comment on the order before it was signed.

Kelly disputed reports that he had not been aware of the order or consulted on it until the last minute. He said that he knew it was being written and saw “at least two drafts” before Friday, and that members of his legal team were involved.

Lori Aratani, Rachel Weiner, Michael Laris and Mark Berman contributed to this report.