U.S. officials went to Afghanistan’s embassy in the District on Monday to turn over historic items that the Afghan ambassador described as “national treasures that form the country’s identity.”

The items were described by U.S. Immigration and Customs Enforcement as five gold artifacts and an ancient vase.

The gold items included three gold foil appliques depicting antelopes and dating to the 5th century B.C. The vase was described as a Roman wine pitcher from the 5th to 8th centuries of the current era.

Monday’s ceremony culminated a process that began in March 2011, when U.S. Customs and Border Protection and the Department of Homeland Security seized a shipment at Newark Liberty International Airport, ICE said.

ICE said the investigation had indicated that items in the shipment were to go to a business suspected of dealing in looted cultural property.

On receiving the artifacts Monday, Afghan Ambassador Eklil Hakimi described them as “extraordinary symbols of our past civilizations.”

Their return, he said, ensured that his country “will once again thrive as a cultural and artistic hub.”

ICE said Monday marked the fourth such event since 2005.