Stolen antiquities taken from billionaire's collection repatriated to Greece

Dozens of stolen antiquities, including "The Kouros," a sculpture valued at $14 million, were repatriated to Greece in a ceremony at the New York District Attorney's office in Manhattan on Wednesday.

"After many years of wandering, they now return to their homeland where they belong," Greek Minister of Culture Lina Mendoni said at the ceremony.

Forty-seven of the antiquities were seized from the collection of billionaire investor and philanthropist Michael Steinhardt in December 2021 after a multi-year, multi-national investigation by the Manhattan District Attorney's office. Another eight items were seized as part of another investigation.

Steinhardt had to give up 180 stolen antiquities, which court records said were looted and illegally smuggled out of 11 countries, trafficked by 12 criminal smuggling networks and lacked verifiable provenance prior to appearing on the international art market.

"On behalf of Homeland Security Investigations, this is a major area that we enjoy investigating and that we need to investigate, and it truly is a privilege to be a part of this grand repatriation ceremony today," said Acting Special Agent in Charge Ricky Patel of Homeland Security Investigations.

The 55 pieces are collectively valued at over $20 million. In addition to "The Kouros," which dates back to 560 BCE, the returned items include a gold broach dating back to 600 BCE that is valued at $1.3 million and a spouted bowl dating back to 2700 to 2200 BCE, valued at $600,000. They come from central Greece, Crete, the Cyclades islands, Samos and Rhodes.

One piece, a larnax -- or small coffin -- from Crete dating back to 1400 to 1200 BCE had been in Steinhardt's office, according to investigators, and when asked about it, he reportedly told an Antiquities Trafficking Unit investigator, "There's no provenance for it. If I see a piece and I like it, then I buy it."

Other items from Steinhardt's collection are being returned to their respective homelands.

"Today is a day of great joy for Greece because all these artifacts, all these items, could be back in the place that borne them, in Greece," Mendoni told ABC News.

Mendoni, who called illegal trafficking a "trauma" in addition to a crime, has been in her role since 2019 and has made the repatriation of Greek antiquities a priority. This includes working to try to get the United Kingdom to return the Parthenon Marbles, which are currently at the British Museum, to Athens.

"I would like to thank, from the bottom of my heart, all the staff of the District Attorney's Office, and of course Matthew Bogdanos for his dedication to this work," she said Wednesday, referring to Assistant District Attorney Bogdanos, who is chief of the Antiquities Trafficking Unit and has Greek roots himself.

After the papers were formally signed to signal the repatriation, Bogdanos called out, "Madam Minister, they're all yours."

ABC News' Aaron Katersky contributed to this report.