This is the best summary I could come up with:
The art unit of Italy's police force found the items had been looted and sold to US museums and private collectors in the 1990s.
The oldest item dates back to the Villanovan age (1000 - 750BC), while other artefacts were from the Etruscan civilisation (800 - 200BC), Magna Graecia (750 - 400BC) and Imperial Rome (27BC - 476AD).
Most artefacts had been stolen in the 1990s, then sold through a series of dealers with one selection apparently being offered to the Menil Collection, a museum in Houston, Texas.
The ministry said the owner of the collection "spontaneously" returned the items after police found that they had come from illegal excavations of archaeological sites.
Separately, the ministry said that 145 of the returned artefacts had come from a bankruptcy procedure against an English antiques dealer, Robin Symes, who amassed thousands of pieces as part of a network of illegal traders.
Italy has long sought to track down antiques and artefacts that have been stolen and sold to private collectors and museums.
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