A staged fire, stabbing, escape and arrest all took place in the three-hour test period, while jail staff scrambled to round up their inmate actors.

The NSW Police, fire brigade, Rural Fire Service and ambulance service all participated in the event, as did staff from the jail itself.

The scenario began with a minimum security prisoner assaulting and murdering a fellow inmate in the jail’s library.

The murderer then set fire to building to destroy the evidence, which resulted in a staff member suffering smoke inhalation and minor burns.

While the diversion was taking place, the escapee was hiding in a shed about a kilometre from the jail’s gates, waiting for a friend to pick him up.

Police and correctional staff tracked the men and subsequently arrested them both.

Wellington Correctional Centre’s regional manager Clarrie Dries said a real prison break was “always” a possibility and staff need to be prepared.

“It can happen anytime ... there are people down there (inmates) that I don’t even know,” he said.

If a real-life situation were to occur, it would require a three-tiered response, with two separate units working from within the jail and one comprised of emergency services staff, he said.

Mr Dries said staff responded “very well” to the dramatised event and even he didn’t know the drill was scheduled until yesterday morning.

“We have to continually review our procedures... And generally hold these (simulations) once every 12 to 18 months,” he said.