Italy ? Masked thieves drilled a tunnel and broke into a jewelry showroom as employees were preparing for a VIP showing in a brazen daylight heist.

Bags of jewels stolen Sunday from Damiani – maker of the diamond bracelet that graced Oscar winner Tilda Swinton’s wrist – included gold, platinum, diamonds and rubies.

The safe normally would have had even more valuable, one-of-a-kind pieces – but a “significant number” were on loan to stars attending the Oscars on Sunday, including Swinton, or in Tokyo for the opening of a new boutique, CEO Guido Damiani said Wednesday.

The losses are being inventoried and Damiani was not issuing estimates.