An ancient limestone bas relief of a Persian soldier with shield and spear was seized by police at the New York edition of The European Fine Art Fair at the Park Avenue Armory.
The relief is worth about $1.2 million and was being offered for sale by Rupert Wace, a well-known dealer in antiquities in London, the New York Times wrote.
The bas relief is a 51.5-square-centimeter piece of carved limestone that was part of a long line of soldiers depicted on a balustrade at the central building on the Persepolis site. It dates to the Achaemenid dynasty – the first Persian empire – and was made sometime between 510 and 330 BC.
Wace said he had bought the relief from an insurance company, which had acquired it legally from a museum in Montreal, where it had been displayed since the 1950s.
The Montreal Museum of Fine Arts displayed the work until 2011, when it was stolen. Three years later, the Canadian authorities recovered it from a collector in Edmonton and returned it to the museum, according to CBC News. But the curators opted to keep the insurance money and let the AXA Insurance Company take possession.
The bas relief is the latest in a string of antiquities the Manhattan district attorney’s office has seized from art dealers and museums in New York City as part of a concerted effort in recent years to recover ancient works.
Experts on artifacts from Persepolis say the bas relief was first excavated in 1933 by a team of archaeologists from the Oriental Institute of the University of Chicago.
The Persian government passed a law in 1930 making it illegal to transport such antiquities out of the country.
According to an earlier statement by  Ebrahim Shaqaqi, the director of legal affairs at the Iran Cultural Heritage, Handcraft and Tourism Organization, the bas relief had been stolen from Persepolis decades ago prior to the 1979 Islamic Revolution.
“Legal follow-ups are underway to first prove that the relic belongs to Iran and finally repatriate it,” said Shaqaqi.   The European Fine Art Fair is an annual art, antiques and design fair, organized by The European Fine Art Foundation in Maastricht, Netherlands.