Mastroianni (1910-1998) was an Italian abstract sculptor. Around 50 items he created, including gold statues and jewellery, have been on display at the Museo d’Annunzio Segreto in Vittoriale degli Italiani, an estate overlooking Lake Garda, since December.
The day before the exhibition was expected to close, managers reportedly discovered the space had been raided, with statues, rings, bracelets, pins and brooches missing.
The items stolen are reportedly valued at €EUR1.3 million ($AUD2.15 million).
The head of the estate, Giordano Bruno Guerri, confirmed that just one piece had been recovered and that authorities were investigating the incident.
“Our alarm systems are very extensive and already of the highest level; we were evidently hit by a highly specialised gang,” he said.
According to a report by local newspaper Brescia Today, thieves entered the museum through a service door and deactivated the alarm.
Umberto Mastroianni's gold jewellery
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