At least 50 people were held Sunday at O'Hare for further questioning, according to lawyers at the scene.
BBC journalist Ali Hamedani left his native Iran in 2009 with no intention of returning to the land that had imprisoned his family.
These days, even though he holds a British passport, Hamedani's birthplace roused enough concern to warrant three hours of questioning at O'Hare International Airport on Sunday, two days after President Donald Trump ordered travel restrictions on seven Muslim-majority countries. During that time officers seized Hamedani's phone and he wasn't allowed to use the bathroom, he said.
"They never used the word detained, so I wasn't under any kind of arrest … but I was questioned two times regarding my place of birth, which is Iran, and regarding my work," Hamedani said. "They ask about my Facebook and they check my Twitter."
Hamedani missed his connecting flight to Los Angeles but considered that a small misfortune compared with the disappointment suffered by a group of LGBT asylum-seekers he met at an airport in Turkey. They had fled Iran for Turkey and were bound for the U.S. until Friday evening's announcement by Trump ruined those plans.
"Their flights are canceled," Hamedani said. "They cannot go back to Iran, and they cannot come to America. I don't know what we can do for them, but at least we can think about them." He added, "Immediately, (when) the news came up, they were crying."
Trump's executive order freezes entry of all refugees to the U.S. for 120 days, halts Syrian refugees indefinitely and places a 90-day moratorium on the arrival of citizens of the predominantly Muslim countries of Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen.
At least 50 people were held Sunday at O'Hare for further questioning, including those from non-Muslim countries like Mexico, according to lawyers at the scene. It was unclear whether the questioning of the Mexican travelers was related to Trump's order.
A 19-year-old German national working in the suburbs as an au pair broke down in tears as she was waiting for her friend, a German citizen born in Iraq, after the friend was held for questioning.
The young women have been in the U.S. working for families since August 2015. They extended their visas to stay another year and were returning Sunday from vacation in Mexico when they were swept up by the new policy.
"I am afraid they won't let her go," said the 19-year-old, who asked not to be identified out of concern for her immigration status. "I think it's crazy. It's discriminating against these people."
The woman is a Muslim who was born in Serbia, a country not affected by the ban. After about an hour, her friend was released.
On Saturday, more than a dozen travelers were placed in custody. All of them had some kind of legal status in the United States, lawyers said. Though all the detainees were eventually released as a result of a court ruling Saturday that effectively suspended some of Trump's travel ban, the presidential directive has stoked fears among the immigrant community — whether they are refugees or permanent residents.
Adding to the confusion, the Department of Homeland Security on Sunday issued a statement saying it will "continue to enforce all of President Trump's Executive Orders" while at the same time vowing to "comply with judicial orders."
For the second straight day, hundreds of protesters occupied an area at Terminal 5 of O'Hare with signs reading "No Ban, No Wall," while chanting slogans like, "Refugees welcome here! No hate, no fear!"
Police stood at the entrances of the arrival doorways and loosely around metal barricades where protesters rallied.
Rozi Bhimani, of Evanston, waved a poster with the image of a woman wearing a star-spangled hijab bearing the words "We the people." The daughter of a Pakistani father, Bhimani said she wanted to vocalize her opposition to the travel ban on Middle East countries.
"I want to send a strong message that we want to see the rule of law and court orders enforced," she said. "I will be very concerned if the executive branch does not listen to the judicial branch."
In Morton Grove, about 500 people packed the basement of the Muslim Education Center on Sunday while hundreds more spilled upstairs and outside the building, during a demonstration calling for sanctuary and support for Muslims and other minority groups against recent Trump administration actions.
"Each day it's imperative we live in concern and know what our government is doing. It's also imperative that we don't live in fear but live in hope, that, as a collaboration, we can make an impact. This march/rally … is to empower all marginalized groups and give hope for the future. We can make a difference together," said Dilnaz Waraich of the Muslim Community Center.
"Our local governments must stand in firm solidarity with our Muslim and Arab neighbors in showing their opposition to these immoral executive orders by passing sanctuary laws declaring their commitment not to cooperate with federal immigration enforcement," said Lesley Williams of Jewish Voice for Peace Chicago.
At O'Hare, more than 150 pro bono attorneys were camped out to aid people who were being held by U.S. Customs and Border Protection.
Attorney Richard Goldwasser said he returned to the airport at 6 a.m. Sunday to offer legal resources to people who may need it.
"We came here today not knowing what to expect, how stringent they were going to apply the executive order, and I'm not sure they know," he said. "One of the problems from the beginning yesterday was the CBP (U.S. Customs and Border Protection) is not giving us any information. Are they holding people? Who are they holding? Their names?"
Trump's executive order garnered sharp condemnation from several prominent figures in Chicago, including Cardinal Blase Cupich, who characterized the measure as "a dark moment in U.S. history."
"The world is watching as we abandon our commitments to American values," Cupich said in a statement. "These actions give aid and comfort to those who would destroy our way of life. They lower our estimation in the eyes of the many peoples who want to know America as a defender of human rights and religious liberty, not a nation that targets religious populations and then shuts its doors on them."
Illinois Attorney General Lisa Madigan denounced Trump's order as "unconstitutional, unAmerican and unlawful" as she joined 15 other attorneys general, including those from California and New York, in opposition to the ban.
"We are confident that the Executive Order will ultimately be struck down by the courts. In the meantime, we are committed to working to ensure that as few people as possible suffer from the chaotic situation that it has created," Madigan said Sunday in a statement.
Also Sunday, Chicago Mayor Rahm Emanuel stopped by the attorneys' table at O'Hare to drop off coffee and pastries. He told the volunteers that the city supports them and that he was working on getting a list of the people who were taken into custody.
U.S. Rep. Robin Kelly, joined by other local officials, addressed the media at a news conference inside the airport wearing a pink "pussyhat."
Kelly said she wants to put pressure on Customs and Border Protection to be more transparent and allow the lawyers access to detainees.
"We are all standing united to help the people being detained. We are very concerned about them," she said.
Trump issued a statement Sunday afternoon defending the travel ban as a step in "keeping our country safe." He said the seven countries named in the executive order were previously identified by the Obama administration as sources of terror.
"America is a proud nation of immigrants and we will continue to show compassion to those fleeing oppression, but we will do so while protecting our own citizens and border," Trump said in the statement.
Abed Aburomman, 29, had been pacing around the terminal Sunday at O'Hare and reading a chemistry textbook as he waited for officials to release his brother, who is Jordanian. Aburomman, a U.S. citizen and a student at Illinois Institute of Technology, was supposed to host him at his home near Midway.
Instead, his brother, who had a visa to stay in the U.S. for 45 days, was sent back to Jordan.
Aburomman, who said he's been living in the U.S. for 10 years, said he understands a country's right to protect its borders but thinks the evaluations should be done on a case-by-case basis. "It's a generalization, it's a stereotype, which is never OK," he said.
Aburomman said he is engaged to be married in August. He doesn't think his family, who live in Jordan, will want to attend his wedding after this ordeal.
Because Jordan was not affected by Trump's travel ban, attorneys said it was hard to say whether he would have been sent back under less tense circumstances.
In the 10 years since Hanan Hameed moved to the U.S., a family friend has traveled back and forth from their native Iraq with relative ease through his green card. When Hameed went to pick him up from O'Hare on Saturday, she ended up waiting for several hours as he and a dozen others were held.
For Hameed, her family was able to secure refugee status in 2007 because her mother worked as a translator for the U.S. government. After five months in Damascus, Syria, Hameed and her family relocated to Charlottesville, Va., where she finished high school and graduated from the University of Virginia.
Even after obtaining her U.S. citizenship and working for the Department of Labor, Hameed questions her future in a country she considers her adopted homeland.
"That's the only thing that bothers me," Hameed, 24, said. "Do invest all my future in this country or should I pack up and leave? It is a problem if I feel I'm living in a country where I will never be accepted. I will always be a Muslim from Iraq. I lived in a place where bad people have done terrible things, but do I have to be painted in the same brush?"
Chicago Tribune's Nancy Stone and Genevieve Bookwalter contributed.