While the most comprehensive sweep of Australia's New South Wales prison system to-date has unearthed mobile phones, drugs and weapons, the use of drones to smuggle in contraband has guards on alert.

Prison staff searched more than 5000 cells in the states' 36 prisons during the 11-week sting dubbed Operation Purge.

Among the items confiscated were 11 mobile phones, 647 grams of tobacco, 44 prison-made weapons, 3.4 grams of crystal meth, 21 buprenorphine strips (a methadone-like drug) and 10 litres of prison brew.

Corrective Services Commissioner Peter Severin told reporters at Sydney's Silverwater Correctional Centre on Monday that prisoners were ingenious in concealing and creating the contraband but he was confident much of it had been rooted out.


"We're getting more sophisticated ways stuff is making its way into the centres, but we're getting far more sophisticated in our response to it."

"Does that mean we will rest? No it doesn't. We will remain relentless in our pursuit of stopping contraband getting into our prisons."

The 105 prisoners found with contraband could serve an extra two years behind bars each, Minister for Corrections David Elliot said.

"That could equate to an extra 210 years that the NSW taxpayers have to fork out to incarcerate these people," he said.

Elliott left the door open for "Purge II" in the future and commended the officers behind the massive operation.

But just one day before the minister announced the results of the search, staff were recovering a drone from the roof of Goulburn Jail.

The broken drone was found along with two packets of tobacco and a mobile phone at 9am on Sunday on the roof of a prefabricated building that had just been moved to Goulburn Correctional Centre from an external storage area, corrective services says.

A few weeks earlier, a drone was captured on CCTV dropping contraband into the Lithgow Prison yard and an inmate was allegedly discovered with 403 steroid capsules a day later.

Prisons in NSW have been aware of the security risk drones pose to prisons, with CCTV and staff surveillance already disrupting their success and payloads rarely finding their way to inmates, Mr Wilson said.

Corrective Services also is looking into multiple drone-stopping technology, with everything from signal jamming, radar guns and mesh canopies over prison yards being considered.