Young inmates at the Brisbane youth detention centre were held in solitary confinement for up 10 days in “disgusting, dirty” overheated rooms with no toilet, bed or running water, a report by the Queensland ombudsman has revealed.

The report also detailed a series of allegations about the management of young people in the months leading up to a 2017 riot at the centre, including claims staff used inmates as enforcers and had “orchestrated” assaults.

While the report did not substantiate specific allegations, it found that based on the weight of evidence it was likely staff had made threats to young people, including that they would be transferred to a unit that housed the “enforcers” and where several assaults had occurred.

“Young people ... became increasingly fearful of [the detainees alleged to have been used as enforcers] following their arrival in November 2016, and formed the perception that they could not rely on staff to protect them from these young people.”

The report chronicled several assaults by a small group of detainees, who had been transferred to Brisbane from Townsville in November 2016, which ultimately led to a riot on 30 January 2017.

After the riot, seven detainees were separated from the main accommodation block at the centre for 10 days. The ombudsman’s report found this was a form of “solitary confinement”.

Six of the children were placed in “admission rooms”, which were typically used like holding cells, to secure young people upon admission to the centre before they were transferred to accommodation.

In interviews, young people described the state of the admission rooms.

“Disgusting, dirty, not even a bed, not even a shower or a toilet; nothing in there at all except a plastic bench,” an unnamed inmate told investigators.

“You’re boxed in … you know what I mean like you can’t do nothing … All you can do is walk up and down four, five steps and you’re walking up and down. That’s it,” said another inmate.

Another detainee said: “They gave us a mattress and then we put the mattress on the floor and slept on there … I don’t think they should be allowed to put kids in a box that long, for that long … being there it affects you more than what you think it would.”

The investigation found the rooms had unacceptably high temperatures and that staff were often not able to respond when young people needed to be let out of the room to use a toilet.

While staff had argued the use of the rooms was necessary after the riot, which had caused damage to other parts of the centre, the investigation found it had also been used at least seven times for extended periods in the two months before that.

The report found there was “insufficient evidence” to justify the continued separation of the seven detainees for 10 days.

“Because of the lack of essential facilities, the admission rooms are clearly unsuitable for accommodating young people for any significant period of time, and particularly overnight,” the report said.