Gang boss' phone found in SuperMax jail

A mobile phone belonging to notorious NSW inmate and Brothers 4 Life boss Bassam Hamzy has been seized inside the state's most high security jail.

A sniffer dog discovered the 3cm-long phone inside the spine of a thriller novel in the library of Goulburn SuperMax prison on Thursday.

A radio with modifications to its internal wiring - a suspected attempt to transform the device into a charger - was also netted during the search.

Hamzy is in the middle of a long stint in jail over a shooting murder in 1998 and for running a drug syndicate and ordering kidnappings from his prison cell.

A full investigation will be launched into how the phone was smuggled into the prison, NSW Corrective Services Commissioner Peter Severin said.

"This is absolutely unacceptable and we will be investigating this incident fully," Mr Severin said.