The returned items include artifacts recently seized in New York from a storage unit belonging to British antiquities dealer Robin Symes, officials said. In addition, the haul that arrived in Rome included 65 objects from Houston’s Menil Collection.

The art unit of Italy’s Carabinieri paramilitary police said the owner of the Houston museum collection “spontaneously” gave back the items after investigators determined they had come from clandestine excavations of archaeological sites, according to a carabinieri statement. The museum did not immediately respond when asked for comment Friday.

Italy has been on a decades-long campaign to hunt down antiquities that were looted by “tombaroli,” or tomb raiders, and then sold to private collectors and museums in the U.S. and beyond. The looting operations involved art dealers who sold the items directly or via auctions.

Some of the items were handed over to Italian authorities Tuesday at the offices of the Manhattan district attorney, Alvin Bragg. Bragg’s office said they included an Apulian krater, or vase, dating from 335 B.C. that was seized in July from a private collection in New York.

The vase had been photographed and included in the famous Polaroid “archive” of dealer Giacomo Medici, who passed it onto Symes, who then “laundered the piece through Sotheby’s London,” Bragg’s office alleged.

Other items included two Etruscan tile paintings from Cerveteri, a frequently-looted necropolis site northwest of Rome, that date back to 440 B.C. .

According to Bragg’s office, the tiles were looted in the 1980s and ended up with Symes, who sold them to noted New York collectors Shelby White and Leon Levy in 1992 for $1.6 million. The couple returned the tiles to Symes before 1999 “after questions about their illicit origins were raised by multiple scholars,” the statement said.

The objects remained in Symes’ New York storage unit until they were seized in March, the statement said.

The Italian police art squad said the value of all 266 pieces, on the open market, would come to tens of millions of euros. The Symes items are in addition to 750 pieces that were in the possession of Symes’ London company, Symes Ltd, which is being liquidated, and Italy put on display May 31.

Symes’ Italy-based lawyers did not immediately respond to an email late Friday seeking comment on the new returns.

In May, before Italy reclaimed the initial trove of 750 objects, Symes’ lawyers, Antonella Anselmo and Giuliano Lemme, said the return was the result of an agreement between the British dealer and the Italian Culture Ministry following “years of complex negotiations and legal proceedings.”

“Under the agreement, hundreds of archaeological finds of great cultural value, which are assumed to have been illegally exported, will return to Italy, where they will be destined for public use,” the lawyers said in a May 11 statement.

The deal also allowed Symes to use proceeds from the sale of some items to satisfy creditors.