Signs that fatigue was setting in had prison officials hopeful that a hostage standoff now in its ninth day could be resolved peacefully, a spokeswoman said Monday.

The two inmates released one of the two guards Saturday, the first major development in the standoff that began Jan. 18. The freed guard, a man, was taken to a hospital; the remaining guard is a woman.

It remained quiet at the scene Sunday night and early Monday, said Corrections spokeswoman Cam Hunter.

"Last night was a lot like many nights recently. There's not as much conversation. It's quieter. That can be the fatigue factor," she said.

Still, she said, negotiations were moving forward.

Negotiators were getting "increasingly more compliant responses" from the inmates, said Ivan Bartos, the Yuma prison warden who has been assisting Department of Corrections officials at the prison in Buckeye.

"Over the past seven days (the inmates) are increasingly doing the kinds of things that we need them to do," he said Sunday as the standoff entered its second week.

On Saturday, the male guard was allowed to climb down a ladder to freedom after negotiators delivered an item demanded by the inmates. As part of the exchange agreement, a second item was delivered after the man went free. Officials did not reveal what the inmates were given.

Negotiators spoke by phone with the woman guard around midday Sunday, and she told them she was all right, said Department of Corrections spokesman James Ahlers. It was the second time they had heard from her since her colleague was released.

Officials at the Arizona State Prison Complex-Lewis (search), in Buckeye, west of Phoenix, have provided little information about the standoff since it began, refusing to discuss how the inmates got into the tower, their possible motive, their previous crimes, their names or the names of the two hostages.

The standoff began after at least one inmate overcame two guards and a worker in the kitchen during breakfast preparation. The inmate then made his way with another inmate to the tower at the edge of a prison yard.

Negotiators have been in contact with the inmates by phone. Until the crisis is resolved, the 4,400 other inmates at the medium- to high-security facility are in lockdown.

Ahlers said the freed hostage was resting and had been reunited with his family at a Phoenix hospital. He gave no details on the man's injuries except to say he would likely stay in the hospital for a few days.

Officials have seen one inmate on the tower's observation deck several times since the standoff began, but saw the other inmate step outside for the first time Sunday, Ahlers said. The inmate, who was wearing a guard's uniform jacket, could been seen pacing and smoking on the deck for a few minutes.