(ANSA) - Palermo, September 25 -Ex-premier Silvio Berlusconi is being investigated by Florence prosecutors in relation to a series of Mafia bombings in 1993, sources said on Wednesday.

The news emerged after Berlusconi's lawyers presented documentation to a court after the media magnate was called to testify in a case involving his jailed former aide Marcello Dell'Utri.

Dell'Utri is a defendant in a trial into alleged negotiations between the State and Cosa Nostra in the early 1990s to stop the Mafia bombing campaign.

Two previous probes into Berlusconi and the bombings were shelved.

The ex-premier's lawyers, Franco Coppi and Nicolò Ghedini, said in a statement that the fact Berlusconi was named as being under investigation was a formality, adding they were confident this probe would be closed too.

