More than 400 children have been rescued from a polygamist sect on a remote Texas ranch amid allegations of forced marriage and sexual abuse.

The children, mostly girls wearing pioneer-era dresses, were removed from the Yearning for Zion ranch yesterday in what authorities described as the largest child-welfare operation in Texas history.

The raid was triggered by a phone call from a 16-year-old girl living in the compound who claimed that she was being abused and that girls as young as 14 were being forced to marry much older men.

Some 133 women, dressed in homemade, full length dresses with their hair pinned up in braids, willingly left the compound along with the children.

State troopers are holding an unknown number of male sect members in the ranch while investigators finished combing the property, owned by the Fundamentalist Church of Jesus Christ of Latter Day Saints.

The probe is not the first time that the sect, which believes polygamy is ordained by God, has found itself in conflict with the law.

In November, Warren Jeffs, its spiritual leader and prophet, was jailed by a Utah court for acting as an accomplice to rape after he forced a 14-year-old girl to marry her 19-year-old first cousin. Sentenced to between 10 years and life, he is currently in an Arizona prison awaiting trial on further charges relating to arranged marriages there.

Yet it was not until last week that the call from the teenage sect member prompted a judge to order the removal of every child on the ranch, deeming them to be at imminent risk of harm.

Local television footage showed the children flooding out of the compound onto buses, which took them to Fort Concho, a 150-year-old fort built to protect frontier settlements. More than 200 staff from Texas Child Protective Services were brought out the small town of Eldorado to conduct one-to-one interviews.

It is not yet clear whether the 16-year-old girl is among them. She allegedly had a child at 15, and authorities were looking for documents, family photos or even a family Bible with lists of marriages and children to demonstrate the girl was married to Dale Barlow, 50.

Under Texas law, girls younger than 16 cannot marry, even with parental approval.

Authorities spoke of the alienation the sect members would likely feel on emerging from the secluded compound, where all the trappings of modern life are eschewed.

“I can’t speculate on what those women are feeling,” Marleigh Meisner, spokeswoman for Texas Child Protective Services, said.

“You can imagine this is a whole new world for them and we’re trying to be sensitive to that,” she told a press conference. Each child would be assigned an advocate and a lawyer, she added.

Ms Meisner would not describe what type of abuse allegedly took place on the ranch but said court hearings will be held in the next two weeks to determine whether the children should be permanently taken from their parents.

Lisa Block, a spokeswoman with the Department of Public Safety, said one person had been arrested at the compound for“interfering with the duties of a public servant” but no one had yet been arrested on charges related to the abuse investigation.

Lawyers for the religious sect yesterday filed an application for a restraining order against the state, called the raid unconstitutional and an “irreparable” desecration of the group’s way of life.

Tensions had earlier risen on Saturday when church members blocked authorities from searching their temple in a stand-off lasting several hours, but police were eventually allowed in without incident.

The sect bought the west Texas ranch for $700,000 in 2003 as authorities in Arizona and Utah, where its enclaves are mostly concentrated, began scrutinising its activities. Residents spend their days raising their large families, tilling small gardens and doing chores. But at least one former resident says life was not some idyllic replica of 19th-century life.

“Once you go into the compound, you don’t ever leave it,” Carolyn Jessop, one of the wives of the alleged leader of the complex, said. Ms Jessop left with her eight children before part of the sect moved to Texas

Ms Jessop said the community practised self-sufficiency because they believed the apocalypse was approaching.

The women were not allowed to wear red - the colour Jeffs said belonged to Jesus - and were not allowed to cut their hair. They were also kept isolated from the outside world.

They “were born into this,” Ms Jessop, 40. said “They have no concept of mainstream society, and their mothers were born into and have no concept of mainstream culture. Their grandmothers were born into it.”

The 1,700 acre ranch is comprised of 30-35 housing units, a medical facility, cement and cheese-making plants, a school, and a number of other outbuildings. The only visible feature from the road, a 24-metre high white limestone temple, rises incongruously out of the brown, dusty scrubland.

Polygamy is outlawed everywhere in the United States but the male followers of such sects typically marry one woman officially and take the others as “spiritual wives.”

This makes the women single in the eyes of the state which can entitle them and their children to various welfare benefits.

The mainstream Church of Jesus Christ of Latter-day Saints, as the Mormon faith is officially known, renounced polygamy more than a century ago and tries to distance itself from breakaway factions that still practice it. Jeffs has headed the FLDS sect since his father's death in 2002.

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