Dallas (CNN) -- Polygamist leader Warren Jeffs remained in critical condition in a Texas hospital on Tuesday, but was not in a coma and is expected to recover, state prison officials said.

Jeffs fell ill while fasting in a prison in Palestine, Texas, where he is serving a life-plus-20-year term for sexual assault, Texas Department of Criminal Justice spokesman Jason Clark said. But while a source familiar with Jeffs' condition told CNN Monday that the leader of the Fundamentalist Church of Jesus Christ of Latter-day Saints was in a coma, Clark said Tuesday that Jeffs was conscious.

"He's somewhat sedated, but he is responsive," Clark wrote.

And Michelle Lyons, another press officer for the department, said Jeffs "is expected to make a full recovery." Lyons said that in addition to not eating, he had "bigger issues that required medical attention."

Prison officials have not elaborated on those conditions, citing inmate privacy rules.

Jeffs was convicted in early August of the aggravated sexual assaults of a 12-year-old girl and a 15-year-old girl he claimed were his "spiritual wives." His church is a breakaway Mormon sect that practices polygamy, which the mainstream Mormon Church renounced more than a century ago.

Jeffs was sent to a hospital in Tyler on Sunday night and was in critical but stable condition Tuesday. He told officials at the Powledge prison unit that he was not on a hunger strike, but had been "fasting," Clark said.

"While he definitely is eating and drinking some, it just wasn't as much as he should," Clark said.

Jeffs' attorney, Emily Detoto, confirmed Jeffs' condition.

Jeffs was also found guilty of two counts of rape by accomplice in Utah in 2007 and was sentenced to 10 years to life in prison there. He had tried to hang himself in jail while awaiting trial there, according to court documents unsealed after his trial.

His church, which is believed to have about 10,000 followers, openly practiced polygamy on a ranch near Eldorado, Texas, and in the twin border towns of Hildale, Utah, and Colorado City, Arizona.

CNN's Vivian Kuo and In Session's Mayra Cuevas contributed to this report.