Thousands of chanting demonstrators blocked roadways, doorways and ticketing areas at airports across the nation Saturday to protest President Donald Trump’s executive order limiting Muslim entry into the United States.

Trump’s order went into effect instantly Friday night, closing borders for at least 90 days to travelers from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen. Several travelers from the targeted countries were suddenly trapped at airports, even if they were holding U.S. government-issued visas or green cards.

In response to the order, demonstrators rallied at airports including New York’s John F. Kennedy International Airport, Chicago’s O’Hare International Airport, San Francisco International Airport, Dallas/Fort Worth International Airport, Seattle–Tacoma International Airport, Los Angeles International Airport and Washington Dulles International Airport. Protesters also demonstrated at airports in Minneapolis, San Diego, Boston and Philadelphia.

Many demonstrators vowed not to leave until travelers detained at the airports were released, and several immigration lawyers arrived at the airports to help trapped travelers.

On Saturday, a Brooklyn federal judge granted a temporary stay against the order after the American Civil Liberties Union filed suit on behalf of two Iraqi nationals who had been detained at New York’s JFK Airport. Still, more protests were scheduled for Sunday.

At JFK on Saturday, hundreds of demonstrators packed roads around the airport and the international arrivals section of Terminal 4. They held signs saying “No ban, no wall” and “Refugees welcome.”

Protesters described the atmosphere as “defiant but orderly” and “very peaceful.”

“We’re here to tell Trump that we are not going anywhere,” lawyer and refugee advocate Jacki Esposito, who helped organize the protest, told NBC 4. “Today is the beginning of a long opposition from us, and our neighbors all over the country.”

The New York Taxi Workers Alliance joined the protest by striking for an hour, adding to the mounting chaos at the airport. The Port Authority temporarily shut down service on the Air Train to the airport after reports said protesters were blocking passengers from exiting, but Gov. Andrew Cuomo ordered service to be restored.

At San Francisco International Airport, protesters mobbed the ticketing area of the international terminal and a roadway outside the airport, police told The Huffington Post. Protesters chanted “Racists out, refugees in,” and sang “This Land is Your Land.”

Angelo Alcid, an intellectual property lawyer who came to SFO to offer any help he could, stood near the arrival gate’s Starbucks offering legal aid to families of detainees. “If I can help in any way, if the most useful thing I can do here is hold up this sign and direct people to experienced immigration attorneys, I’m happy to do that,” Alcid said.

Nazli Nadem, of nearby San Ramon, immigrated to the United States from Iran five years ago. Nadem said she came to the airport to show her support for refugees and those detained. “I respect the United Stares and that they want to keep their country safe. But this is not the way,” Nadem said.

Singing breaks out at the SFO #muslimban protest. No signs of this winding down yet. pic.twitter.com/FEVqvfMdUO — Mollie Reilly (@MollieReilly) January 29, 2017

Chicago was forced to close down all traffic to international Terminal 5 due to a protest there.

Northwestern law student Jamie Zucker was among the volunteer legal aides at the airport with the International Refugee Assistance Project. Attorneys were working to free the estimated dozen travelers detained there, Zucker told HuffPost.

Reunion at #ord now. Crowd chants “she is what America looks like” pic.twitter.com/wv6eqne7pu — Kim Bellware (@bellwak) January 29, 2017

Hundreds of protesters were also gathered at Dallas International Airport. Several people were waiting for family members who were being detained by immigration officials.

“This is not America,” one man waiting for his son told the Dallas Morning News. The city’s mayor, Mike Rawlings, called Trump’s order “bad for the heart.”

The crowd at @DFWAirport keeps growing. One traveler said 30-40 people still being held pic.twitter.com/l6jX6DgeFz — Julieta Chiquillo (@jmchiquillo) January 29, 2017

Hundreds of protesters also descended on Los Angeles International Airport, where at least seven travelers from the targeted countries were being detained, even though each held a U.S.-issued visa or green card.

One of the travelers was an Iranian woman whose citizenship swearing-in ceremony was scheduled to take place in two weeks, immigration attorney Jordan Cummings told the Los Angeles Times.

The scene at Boston's Logan Airport right now pic.twitter.com/eDrSlNfQL3 — i have died (@ChrisCaesar) January 29, 2017

Mollie Reilly reported from San Francisco, Kim Bellware in Chicago, Daniel Marans and Ben Walsh from D.C., and Omar Kasrawi and Sebastian Murdoch from New York.