Child welfare workers have taken custody of 52 girls from the Fundamentalist LDS Church's compound in Eldorado, Texas, after a raid over allegations of child sex abuse on the Utah-based polygamous sect's ranch.

"We legally removed 18 children. We concluded they had been abused or were at immediate risk of future abuse," said Darrell Azar, a spokesman for the Texas Department of Family and Protective Services. "Under Texas law, either one is grounds for removal."

An additional 34 girls were taken Friday afternoon to the nearby city of San Angelo, where they are being interviewed to determine if they should be placed in state protective custody.

Police are also serving warrants in connection with the investigation.

"At this point we are now serving search and arrest warrants at the property for individuals covered in those warrants," Texas Department of Public Safety spokesman Tom Vinger said. "Nobody's been arrested at this time."

The San Angelo Standard-Times is reporting that a warrant was unsealed in district court, naming 50-year-old Dale Barlow and accusing him of marrying and fathering a child with a 16-year-old girl at the ranch.

Texas child protective services workers were on the YFZ Ranch Thursday and Friday, interviewing the children who live there. Authorities said the investigation began when a 16-year-old girl who lives there called child protective services on Monday.

"She said she was being sexually abused," Schleicher County Attorney Raymond Loomis told the Deseret Morning News.

Azar said the girl also claimed to have suffered physical abuse.

State and local law enforcement officers went to the ranch late Thursday with an armored personnel carrier, the Eldorado Success newspaper reported. Police blocked off the entrances and exits to the compound.

"We are there to assess the safety of these children," said Marleigh Meisner, a spokeswoman for the Texas Department of Family and Protective Services.

Authorities said the FLDS people on the ranch are cooperating.

"They're being cooperative and providing us with all the people we need to speak to," said Vinger. "It's sensitive, but it's going well."

The YFZ Ranch is the site of the polygamous sect's first-ever temple, which was completed in 2006. "YFZ" stands for "Yearning for Zion," after a song penned by FLDS leader Warren Jeffs.

The group purchased the property in 2003 under the guise that it would be a "hunting retreat." Since then, a small city has been built on the outskirts of Eldorado, a western Texas prairie town. Few outsiders are allowed onto the ranch, but based on the view from small airplanes, the growth of the YFZ Ranch has been documented. Men, women and children are seen working in the fields or constructing buildings.