Gang founder and convicted murderer Bassam Hamzy single-handedly ran the deadly Brothers for Life using a mobile phone smuggled in to his Lithgow maximum-security cell in 2008.

He made a staggering 19,523 calls in six weeks, running a $250,000-a-week drug ring, ordering shootings, bashings and kidnappings and threatening to cut one man's ears off "and make them into a necklace".

Corrective Services NSW has ramped up security at Silverwater jail following the latest incident but will not commit to rolling out mobile phone jamming technology.

Acting on intelligence, a senior corrections officers from a specialist squad searched Mohammed Hamzy's cell in Silverwater jail on July 19 and spotted what he thought was a USB sitting on the base of a television.

"Further searches of the cell revealed a key ring-shaped mobile phone and charging device within the wall," an agreed statement of facts tendered in Burwood Local Court said.

Hamzy, known as "Hamoudie" and "Little Crazy", made admissions to owning the mobile phone and the charger but, when interviewed by police, claimed it was a car key.

"It's BMW, it's mine," he said.

A police source told The Sun-Herald that the device was a BMW key ring phone, a working phone disguised as a BMW car key and sold for as little as $30 from China.

Cousins Bassam, Mohammed and Ghassan Hamzy founded the Brothers for Life while in prison together around 2008.

Mohammed, the leader of the gang's Bankstown chapter, has been in custody in Silverwater jail since November 2013 awaiting trial for the murder of fellow gang member Yehye Amood and wounding of another man, who were shot while sitting in a Mercedes with B4L number plates in Greenacre in 2012.

Hamzy, 29, told officers that he had only had the phone for "a couple of days" but a Corrective Services spokesman would not confirm this.

The spokesman would not say how many calls and messages were sent by Hamzy and to whom. Hamzy was placed in segregation, he said.

Perimeter fences at Silverwater have been upgraded in recent months to prevent items being thrown into the jail, said Commissioner Peter Severin.

He said random cell searches are conducted daily and the Corrections Intelligence Group routinely provides information to the specialist search squad, the Security Operations Group, to conduct targeted searches.

Mobile phone sniffer dogs and new mobile metal detectors are also utilised and all visitors are screened.

"Contraband mobile phones, including mini key ring phones, are an issue for correctional jurisdictions around the world," Commissioner Severin said. "NSW is no different."

Following the conclusion of a mobile phone jamming trial in Lithgow prison in September, Corrective Services is preparing a report for the Australian Communications and Media Authority, which will decide if it will be rolled out in all prisons.

Hamzy pleaded guilty in Burwood Local Court on Wednesday to possessing a mobile phone and SIM card and will be sentenced in December.

He was arrested for murder on November 7, 2013, at the height of a bloody internal dispute between the Bankstown and Blacktown chapters that resulted in two murders, 11 shootings and two knee-cappings.

All the key Brothers for Life members are now in custody yet Deputy Police Commissioner Nick Kaldas told the Sun Herald last week that there is still the possibility of gang activity continuing on the outside.