Polygamist sect leader Warren Jeffs was found "convulsive," weak and feverish in an Arizona jail cell before he was hospitalized under tight security in Las Vegas , a sheriff's spokeswoman said Wednesday.

The 52-year-old president of the Fundamentalist Church of Jesus Christ of Latter Day Saints was found Tuesday "in a weakened state of health, acting in a convulsive manner, shaking, and running a fever," said Trish Carter, spokeswoman for Mohave County Sheriff Tom Sheahan.

Jeffs was first taken from jail to Kingman Regional Medical Center in Arizona , and then flown by medical helicopter about 100 miles to Las Vegas .

Jeffs is charged in Arizona as an accomplice with four counts of sexual conduct with a minor stemming from the marriages of two girls. He also had been charged with four counts of incest as an accomplice, but those charges were dropped last month.

He heads the FLDS, an insular faith of nearly 6,000 followers that practices polygamy in arranged marriages that have sometimes involved underage girls. One of their ranches was raided in west Texas in April, setting off a lengthy legal battle over the custody of hundreds of children.

Jeffs had "sporadic eating habits" and may have lost weight in the 133 days he was held in the Mohave County jail in Kingman, Carter said. But Carter said she could not say Jeffs had been fasting as he did while jailed in Utah over the past two years.

"This is our watch. He's our inmate," Carter said. "Our job is to ensure he's in good health and ready to go to trial. If he has any medical conditions, we are going to have deputies and detention officers make sure he's safe and healthy."

Jeffs' Arizona lawyer, Mike Piccarreta of Tucson , acknowledged that Jeffs was hospitalized, but refused to say why.

"I really don't want to comment on his personal medical condition," Piccarreta said.

Carter said Jeffs has been jailed in what she called protective custody for his safety and to prevent escape. He was kept alone in his cell for 23 hours a day, and allowed one hour of recreation while remaining segregated from other inmates.

Jeffs was convicted by a Utah jury last year of two counts of first-degree felony rape as an accomplice. He was sentenced to two consecutive terms of five years to life in prison for his role in the 2001 marriage of a 14-year-old follower to her 19-year-old cousin.

The sect leader has had several health complications in prison, including a trip to a Utah prison infirmary in February 2007 because of a self-imposed fast.

Utah court documents show that Jeffs lost 30 pounds fasting while in jail awaiting trial, and that he was hospitalized for treatment of fasting, dehydration and sleep deprivation.

A clinical social worker who interviewed Jeffs reported that Jeffs attempted to hang himself in January 2007.