SAN ANGELO, Texas — Revelations that the March 29 phone call that sparked a raid on a west Texas polygamist compound may be a hoax have led prosecutors to doubt the reason for the original search-and-arrest warrant that granted authorities access to the Yearning for Zion Ranch.

Arrests still could be made in the case, said first assistant 51st District attorney Allison Palmer. The raid, based on the warrant, led to the removal of 437 children from the Fundamentalist LDS Church ranch, the largest child custody action in Texas history.

"If it were true that the female who identified herself as Sarah is not really Sarah, I do not feel that would be enough to (invalidate) the search warrant," Palmer said.

Even so, "some events have shaken our belief and confidence in that probable cause," she said. Palmer used the phone calls as the probable cause necessary to secure the warrant granted by District Judge Barbara Walther.

Nevertheless, she added, the criminal investigation continues and still could result in arrests — even if the original reason turns out to be faulty. The arrest warrant remains active, she said, and prosecutors have not decided whether they will file a motion to withdraw or dismiss it.

"Probable cause is just that," Palmer said. "You're not dealing with certainties. You're dealing with probabilities."

Colorado authorities and the Texas Rangers are investigating whether a Colorado Springs resident made the series of phone calls March 29 and 30 that led the NewBridge Family Shelter in San Angelo to contact the state's Child Protective Services agency and relay her claims of physical and sexual abuse at the ranch.

Questions about the phone calls' legitimacy have arisen as three weeks have gone by without any identification of the 16-year-old girl who allegedly made the calls. The man she identified as her "husband," Dale Barlow, 50, has denied wrongdoing. The Texas Rangers visited him recently, but he has not been arrested in the case.

Investigation into the false-report allegations is ongoing, said Tom Vinger, spokesman for the Texas Department of Public Safety, downplaying somewhat the significance of the same person's arrest on separate misdemeanor false-reporting charges.

"If we knew that (she made the March 29-30 phone calls), we would have filed an arrest warrant for her," Vinger said. "People can read in what they want to read."

As news of that arrest and possible involvement in the case was reported last week, CPS officials backed off their insistence that the girl would be found.