The United States has returned 25 artefacts that were looted from Italy, including Etruscan vases, 1st-century frescoes and precious books that had made their way into top US museum, university and private collections.

A detail of the cover of a second century Roman marble sarcophagus, representing a woman, is seen as it's displayed during a press conference in Rome.

A detail of the cover of a second century Roman marble sarcophagus, representing a woman, is seen as it’s displayed during a press conference in Rome. Image by (AP Photo/Alessandra Tarantino)

The items were either spontaneously turned over or were seized by police after Italian authorities noticed them in Christie’s auction catalogues or gallery listings and tipped them off.

One 17th-century Venetian cannon was seized by Boston border patrol agents as it was being smuggled from Egypt inside construction equipment.

A Carabinieri Italian paramilitary police officer stands next to ancient artifacts returned to Italy by The United States, on display in a Rome Carabinieri barracks.

A Carabinieri Italian paramilitary police officer stands next to ancient artifacts returned to Italy by The United States, on display in a Rome Carabinieri barracks. Image by (AP Photo/Alessandra Tarantino)

US ambassador John Phillips joined Italy’s Carabinieri police to show off the haul, which included Etruscan vases from the Toledo Museum of Art and the Minneapolis Institute of Art, and 17th-century botany books from Johns Hopkins University.

The items also included a manuscript from the 1500s stolen from the Turin archdiocese in 1990 that ended up listed in the University of South Florida’s special collections.

A first century B.C. fresco taken from Pompeii. The United States has returned 25 artifacts that were looted from Italy, including Etruscan vases, 1st century frescoes and precious books that had made their way into top-notch U.S. museum, university and private collections.

A first century B.C. fresco taken from Pompeii. The United States has returned 25 artifacts that were looted from Italy, including Etruscan vases, 1st century frescoes and precious books that had made their way into top-notch U.S. museum, university and private collections. Image by (AP Photo/Alessandra Tarantino)

“Italy is blessed with a rich cultural legacy and therefore cursed to suffer the pillaging of important cultural artefacts,” Mr Phillips said, adding that Interpol estimates the illicit trade in cultural heritage produces more than nine billion dollars (£5.8 billion) in profits each year.

Police said several of the items were allegedly sold by Italian dealers Giacomo Medici and Gianfranco Becchina, both convicted of trafficking in plundered Roman artefacts. After the objects were recovered, Italian authorities confirmed their provenance.

A Carabinieri Italian paramilitary police officer stands next to a group of ancient artifacts returned Italy by The United States, on display in a Rome Carabinieri barracks.

A Carabinieri Italian paramilitary police officer stands next to a group of ancient artifacts returned Italy by The United States, on display in a Rome Carabinieri barracks. Image by (AP Photo/Alessandra Tarantino)

Police stressed that most collectors and museums willingly gave up the artefacts after learning they had been stolen. The Minneapolis museum director contacted the Italian culture ministry after reading an article about one suspect piece, police said.

Mr Phillips praised the collaboration between Italy’s police and US homeland security and border patrol agents.

He also said the US had returned more than 7,600 objects to over 30 countries and foreign citizens since 2007.

(Press Association)