SAN FRANCISCO (AP) — Hundreds of demonstrators protested Tuesday outside U.S. Immigration and Customs Enforcement offices in San Francisco, banging drums and chanting, “Stop taking children!” as uproar grew over the Trump administration’s policy of separating immigrant children from their parents.

Some in the group of about 500 held signs that read, “Refugees In, ICE Out” and “Keep Families Together.”

“Our country was built on immigrants, and they are denying them basic human rights and treating them inhumanly,” said Algazzali Gonzalez of Albany, who held her 9-year-old daughter on her shoulders.

The schoolteacher said she joined the demonstration because she has been angry about the separation of families. Her daughter, Yazmin Gonzalez, held a sign that read, “Children Need Their Parents.”

“People need to understand how angry we are. People need to hear how upset we are,” Gonzalez said.

More than 2,300 children have been separated from their parents from May 5 through June 9, federal officials said, as part of a Trump administration effort to deter illegal border crossings. They have not specified how long the youngsters will be held.

The government is prosecuting all illegal crossing, sending parents to jails and children to facilities run by the Department of Health and Human Services.

The agency has defended its operations, saying that younger children in its care are being placed in “permanent shelters” where they receive education, clothing, medical and mental health services, and recreational and entertainment opportunities.

High school teacher Craig Clouden of Santa Cruz also demonstrated Tuesday against the policy.

“I felt like I had to take a stand against a grave human rights violation,” he said. “It’s so severe, it’ll damage the children and the country in ways we can’t even see.”