Nine of 10 prisoners who escaped from an Australian jail on Tuesday have been recaptured, police say.

The men had broken out of Greenough Regional Prison, 400km (250 miles) north of Perth, during what staff described as "a riot".

It prompted police to send text messages to the public, warning them to treat the men as "unpredictable".

Police said on Wednesday that only one prisoner, 35-year-old Bradley Silvester, remained at large.

The 10 medium security inmates had used ladders to escape the jail during a disturbance late on Tuesday, prison officials said.

"[The disturbance] started with a cell fire and then there were a couple of other fires lit in the prison," Corrective Services Commissioner Tony Hassall told The West Australian newspaper.

"They broke into some staff offices, got some equipment and used that to cause some damage."

He said inmates had also assaulted prison officers with unidentified equipment. According to the officers' union, three guards were attacked with chemical spray.

"Our members are describing the incident as a riot," union secretary Paul Ledingham told the Australian Broadcasting Corp.

"Reports this morning are there is extensive, extensive damage within the prison."

More than 150 extra police officers were deployed to the region to help track down the escapees.

Western Australia Premier Mark McGowan called it a "very dangerous and very fluid situation".

Locals were sent late-night messages after the breakout, warning them to keep their homes and cars locked.

Five prisoners were recaptured on Tuesday. Another four - Devon Comeagain, Alan McDonald, Brendan Bartley and Darryl Councillor - were returned to custody on Wednesday.

Authorities did not say what sparked the disturbance. Union officials have alleged that the jail is overcrowded, with "unsustainable" levels of staffing.