SAN ANGELO, Texas (CNN) -- The Texas branch of the American Civil Liberties Union said it was concerned that the basic rights of the children and mothers connected to a Texas polygamist ranch were violated during a recent raid and custody hearing.

At the hearing Friday, Judge Barbara Walther ordered 416 children connected to the YFZ (Yearning For Zion) ranch kept in state custody.

Walther made her ruling after two days of testimony at the hearing, which was aimed at determining whether child welfare authorities properly removed the children from the sect's Texas ranch. The judge said she found sufficient evidence for Texas Child Protective Services to retain custody of the children.

The ACLU said it had a representative at the court hearing and the organization was concerned about human rights violations.

"While we acknowledge that Judge Walther's task may be unprecedented in Texas judicial history, we question whether the current proceedings adequately protect the fundamental rights of the mothers and children," Terri Burke, executive director of the ACLU of Texas, said in a written statement.

"As this situation continues to unfold, we are concerned that the constitutional rights that all Americans rely upon and cherish -- that we are secure in our homes, that we may worship as we please and hold our places of worship sacred, and that we may be with our children absent evidence of imminent danger -- have been threatened," Burke said.

The group's courtroom observer, Lisa Graybill, added: "We recognize that this balancing act is difficult, but we are concerned that government may not be complying with the Constitution or the laws of Texas in the execution of its mandate, from how the raids were conducted to whether the current process protects basic rights."

The ACLU statement did not list any specific instances of human rights or constitutional violations, and ACLU representatives did not immediately return calls seeking comment.

Child Protective Services spokeswoman Marleigh Meisner said her department is in the process of finding "temporary placement" for all the children. "What we did was warranted and in the best interest of the children," she said. "This is not about religion -- this is about keeping children safe from abuse."

The hearing stems from an April 4 raid of the ranch, which authorities said was triggered by phone calls in late March from a 16-year-old officials referred to as Sarah. The caller said she had been beaten and forced to become a man's "spiritual" wife.

On Thursday, child protection supervisor Angie Voss testified that she and other investigators encountered several pregnant teenagers at the YFZ ranch, which is in Eldorado, Texas, about 40 miles outside San Angelo. The girls called each other "sister wives," Voss said, and believed it was acceptable to be "spiritually united" with a man at any age. "It was the belief that no age was too young to be married," she said.

Members of the ranch have denied the girl, supposedly named Sarah Jessop Barlow, exists, and authorities have yet to find the caller. However, Texas Rangers are pursuing a Colorado woman as a "person of interest" regarding the phone calls that touched off the raid.

Authorities on Friday said a search of Rozita Swinton's home in Colorado Springs resulted in evidence that possibly links her to phone calls made about the YFZ ranch. Swinton, 33, has been charged in Colorado with false reporting to authorities, but police said that the arrest was not directly related to the Texas case. E-mail to a friend

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