Attorneys ad litem for 18 girls from the Fundamentalist Church of Jesus Christ of Latter Day Saints who are in the legal custody of the state had sought the order, said Marissa Gonzalez, a spokeswoman for Texas Child Protective Services.
The attorneys reasoned that cutting off communications would "prevent the possible tampering of witnesses," Gonzalez said, reading from the court document.
It was unclear how many phones were taken Sunday. Gonzalez did not know if the document could be released.
Some 416 youngsters were rounded up and placed in temporary custody 11 days ago, after a domestic violence hot line recorded a complaint from a 16-year-old girl who said she was physically and sexually abused by her 50-year-old husband.
Affidavits filed by child protection workers said that, upon investigating, they found a pattern of abuse existed at the Yearning for Zion ranch in Eldorado, about 45 miles south of San Angelo.
The 1,700-acre fenced ranch, a former game preserve, was bought by the FLDS in 2003.
A number of large dormitory-style homes have been built, along with a small medical facility, a cheese factory, a rock quarry, water treatment plant and a towering, white limestone temple.
The children are currently being housed in San Angelo's historic Fort Concho and at the nearby Wells Fargo pavilion. About 140 women from the ranch are also with the children, although they are not in state custody.
On Saturday, five FLDS women staying at the fort told the Salt Lake City-based Deseret News the temporary shelter is cramped - cots, cribs and playpens are lined up side-by-side - and that many of the children are frightened.
Authorities said they have not yet located the teenage mother whose call for help triggered the raid at the ranch.
Texas Rangers met with Barlow and his probation officer in St. George, Utah, on Saturday, but did not arrest him.
Barlow is serving three years probation after pleading no contest to sexual misconduct with a minor - a teenager to whom he was spiritually married.
"As for Mr. Barlow, we are continuing to look into whether we have a warrant on the correct person," said Tela Mange, spokeswoman for the Texas Department of Public Safety.
Mange said it would be difficult to know the suspect's correct identity until they talk with the 16-year-old girl.
The secretive sect practices polygamy in arranged marriage that often pair underage girls with older men. The faith believes the practice will brings glorification in heaven.
A judge will decide this week if the children will remain in state custody or return to their families. Hearings are scheduled for Monday and Thursday.