U.S. Customs and Border Protection officials at O’Hare Airport released three American citizen children to their undocumented mother late Thursday afternoon. The children, all girls, ages 9, 10 and 13, had been held at the airport for more than 12 hours.

Immigration lawyers, a representative from the Mexican Consulate and a congresswoman from Illinois met with federal officials at different points throughout the afternoon arguing for the release of the children. In addition, several advocates gathered at the international terminal at O’Hare for hours rallying in support of the family.

After reuniting with her daughters, the girls’ mother told reporters that she was afraid that she would be deported if she came to airport. The girls had been held there since 3 a.m. when they arrived from Mexico with a cousin. The cousin was also detained and, ultimately, ordered to return to Mexico.

“In the morning I said, let me go pick them up but then I realized that our rights are not respected,” said Silvia, the girls’ mother, who would only give her first name.

U.S. Customs and Border Protection officers deemed the cousin “inadmissible,” according to a statement issued Thursday afternoon by a department spokesperson. The statement didn’t offer further details about the cousin’s status. “U.S. Customs and Border Protection Officers have attempted numerous times today to reach family members to pick up the children. As of 2 pm [Central time] CBP Officers are still awaiting a legal guardian to arrive and pick the children up,” the statement read.

Silvia arrived at the airport late Thursday afternoon accompanied by Mony Ruiz-Velasco, executive director of PASO West Suburban Action Project; Rodrigo Baez, the counsel of protection with the Mexican Consulate in Chicago; and Congresswoman Jan Schakowsky.

Silvia left the airport with her three daughters without incident. Federal officials said that the girls were provided food and drinks. And Silvia said the girls were in good spirits. Silvia thanked the Mexican consulate, lawyers and community activists who rushed to the airport to help.

Initially, activists decried the move to hold the children. Some claimed that federal officials were setting a trap for their parents.

“This is yet another example of the abusive practices and disregard of the law,” said Ruiz-Velasco, who said she was notified of the situation by the Mexican Consulate. “They have three U.S. citizen young girls detained, causing trauma and harm to this family and our communities.”

Ruiz-Velasco said she presented a letter from the parents earlier in the afternoon authorizing federal officials to release the children to her. But officials refused to do so, she said.

While awaiting a resolution, some activists created signs at the airport to show support for the family. “Don’t make children hostages,” one sign read. “Let the children go,” read another sign.