Ingroia investigated for possible leak
Provenzano's family accuse former prosecutor of releasing news08 October, 18:19
Prosecutors in Palermo are investigating whether Ingroia leaked information about Provenzano following a complaint filed by Provenzano's adult children and his lawyer.
They say that information was given to the media which only someone involved in interviews with Provenzano - such as the prosecutor - could have known.
Arrested in 2006 after 43 years on the run, Provenzano has been subjected to the so-called 41-bis treatment for Italy's most dangerous criminals.
They can be kept in single-person cells in maximum-security jails, almost entirely cut off from the outside world in order to prevent further criminal activity.
The ex-mafia chieftain, once nicknamed "The Bulldozer", is serving life for various murders including ordering fatal bomb attacks on anti-mafia prosecutors Giovanni Falcone and Paolo Borsellino in 1992.
Provenzano has been fighting for a transfer from the top-security prison regime due to his declining health.
However, his requests have been rejected.
Ingroia left his career as a prosecutor earlier this year following a disappointing foray into politics in February's general elections.
He is set to start a new career as a defence lawyer in Rome.