Yesenia immediately called her neighbors to warn them that immigration officers were outside their Compton apartment building. Then she watched in tears as officers handcuffed her father and took him away.
During the three weeks he was detained, Yesenia said, her schoolwork suffered and she could barely sleep.
"I thought, 'I'm never going to see my dad again,' " said Yesenia, a U.S. citizen by birth.
As federal authorities expand immigration enforcement in California and throughout the nation, teachers, mental health professionals and immigrant rights advocates are raising concerns about the effect on children like Yesenia who are U.S. citizens.
Last month, a California congresswoman held a hearing on the raids' consequences for children.
"The administration must take the necessary steps to ensure that these raids are conducted in a humane fashion and they are protective to kids, not harmful," said Rep. Lynn Woolsey (D-Petaluma).
During the hearing, an elementary school principal from the Bay Area city of San Rafael, testified that local immigration raids in 2007 traumatized children and resulted in high absenteeism and low test scores.
National Council of La Raza President Janet Murguia testified that immigration agents instilled fear among children by conducting enforcement operations near public schools and Head Start programs. The Latino civil rights organization released a report last year that found several children were left to fend for themselves when their parents were detained.
According to the report, about 5 million children in the U.S. have an undocumented parent and two-thirds of those children are U.S. citizens.
Immigration and Customs Enforcement officials say they strike a balance between enforcing the law and humanitarian issues that arise during enforcement.
Last year, the agency worked with Sen. Edward Kennedy (D-Mass.) to set new humanitarian guidelines for large work-site raids and to consider making special arrangements for certain people who are arrested, such as nursing or pregnant mothers or immigrants who serve as sole caregivers to children or seriously ill relatives.
They also issued a memo directing agents not to take children into custody if they are U.S. citizens or legal permanent residents and instead try to coordinate care with child welfare authorities.
Spokeswoman Virginia Kice said the federal agency goes to extraordinary lengths to address family concerns. But once an immigration judge has determined that a person does not have a legal right to be in the United States, the agency is going to carry out the judge's order, she said.
"They have violated our laws," Kice said. "It's no different than if they have violated other laws. There are consequences for that."
Advocates who favor stricter controls on immigration said illegal immigrant parents not the government are to blame.
"The impact on their children is their responsibility, not ours," said Barbara Coe of the California Coalition for Immigration Reform.
Ron Prince, an anti-illegal-immigration activist, said he sympathizes with the children but that the government cannot make exceptions for families.
"By not enforcing our law, we encourage people to break it," he said.