Turkey has put on display Roman-era mosaics that were part of a U.S. university's art collection and were returned to the country more than half a century after looters smuggled them out.

At a ceremony on Saturday, Culture Minister Mehmet Nuri Ersoy thanked Ohio's Bowling Green State University administrators and others who were instrumental in the return of the artifacts. Archaeologists discovered the mosaic, known as Gypsy Girl, 20 years ago while excavating the remains of the city of Zeugma, founded by a general of Alexander the Great and destroyed in the 3rd century, BBC News reports.

However, several pieces had already been looted and smuggled out of the country.

Get Breaking News Delivered to Your Inbox

Bowling Green bought the 12 mosaics from a New York gallery in 1965. Turkey asked for their return in 2012, and Turkish and Bowling Green officials agreed up on their return in May after finally agreed after five years of talks, BBC News reports.

U.S. Embassy diplomat Jeffrey Hovenier said Saturday: "We are delighted to welcome home part of Turkey's glorious heritage."

The mosaics are being exhibited at Gaziantep's Zeugma Mosaic Museum.