Tensions remain high in New South Wales jails as authorities work to prevent coronavirus spreading through the prison system.
There have been several disturbances in recent weeks, including riots at Wellington and Goulburn during the Easter break.
Gas was used by prison guards to subdue the prisoners at Wellington Correctional Centre, in the state's central west, after inmates started a fire and destroyed equipment.
"It is fairly tense within the prison system," Public Service Association (PSA) general secretary Stewart Little said.
"You've had around a month now where there's been no access visits with family members — it's really only essential visits."
'Heightened emotions'
All visits have been cancelled to stop a COVID-19 outbreak in the state's prison system.
"It comes with consequences," Mr Little said.
"Of course many, many inmates are very agitated, very tense, given that the fact that it's now been over a month since there's been contact visits."
The PSA said authorities were working hard to avoid coronavirus outbreaks like those that had occurred in prisons in New York and the United Kingdom.
Corrective Services NSW said inmates were feeling "frustrated" and were "experiencing heightened emotions" because their routines had been disrupted.
There are about 14,000 inmates in prisons across the state.
Some 1,200 virtual visits have been conducted so far.
A spokeswoman for Corrective Services said that practice would continue.
Contraband shortage
The restrictions also mean that illicit goods like tobacco and illegal drugs are not making it into prisons.
"You have inmates that are extremely dangerous, violent inmates, many with sentences that are going to see many of them never get out," Mr Little said.
"They are very, very difficult to manage at the best of times, but when you then further restrict them obviously that becomes even more difficult."
Mr Little said it was a significant achievement that there had been no confirmed cases of coronavirus in NSW prisons.
"It shows the dedication and professionalism of all of the Corrective Services staff," he said.
The PSA says planning is underway for worst-case scenarios, including the use of isolation hubs and field hospitals to group prisoners diagnosed with COVID-19.
