Prisoners at Westgate staged an overnight sit-down in protest at the medical treatment offered to an inmate.

The demonstration began at about 9 p.m. on Wednesday and involved about 20 men in the E2 unit of the jail. It had ended by 5 p.m. yesterday.

Bryan Payling, Commissioner of Corrections, described the sit-down as a "passive demonstration" which ended with no injuries to staff or prisoners.

But he revealed that extra staff had to be drafted in to deal with the situation after the men refused to return to their cells to be locked in on Wednesday night.

"The prisoners said they weren't going back to their cells and sat down. There is a big open space in the unit ? they were in that area. They were told to return to their cells. We deployed staff to monitor the situation."

Mr. Payling, who has been in his post for just two weeks, said those involved were "supporting a prisoner whose views of his medical needs differed from that of the medical staff at Westgate".

He would not give details of the prisoner or his ailment but said that a member of staff assessed him on Wednesday and decided he did not need emergency treatment, as he was insisting.

"It was a very clear medical view that there was no requirement for him to be admitted to the emergency room," said Mr. Payling.

"One of the things that the staff were intervening to do was to reassure the prisoner himself and the prisoners supporting him that treatment had been offered and refused and that the prisoner would have another opportunity to see the doctor.

"That was not taken on board and the prisoners persisted with their demonstration throughout the night. As the night progressed the numbers tailed away as they went back to their cells."

Mr. Payling said 14 prisoners plus the ill inmate were still protesting yesterday morning. "He saw the doctor. The doctor determined what was necessary. The prisoner didn't agree but as the day progressed the numbers sitting out slowly reduced. They returned to their cells."

He would not say how many extra staff were called in but said officers were instructed to try to avoid any physical confrontation.

"I was satisfied that we had enough staff available to deal with the incident. The night passed, as did the day, peacefully and clearly in these situations one doesn't want to escalate it in any way and put people at risk," he said.

"All of the prisoners have now either returned to their cells or have moved to other places under assistance and there has been no force necessary to restrain prisoners.

"One or two men might have had to be assisted along but there was no resistance that required force to be used. I'm happy that we have arrived at a conclusion that has resulted in prisoners no longer protesting."

Mr. Payling said he was satisfied that the prisoner's medical needs were being met. He added: "When we go to the doctor it's not for us to decide what our treatment should be. I have got no reservations about saying that Westgate provides appropriate medical treatment and appropriate medical advice to the patients there."