VIENNA, June 12 (Reuters) - Austrian prosecutors said on Friday they were bringing a case against former tycoon Rene Benko, who founded the now-collapsed Signa property group, for aggravated fraud and insolvency-related fraud.

"The prosecutors' office accuses Benko of providing a false guarantee to an investor and/or representatives of a family trust and fraudulently causing the trust harm to the value of around EUR5 million euros ($6 million)," the Central Prosecutors' Office for Economic Crimes and Corruption said in a statement.

($1 = 0.8639 euros)

(Reporting by Francois Murphy; Editing by Kevin Liffey)