LOS ANGELES (AP) — The J. Paul Getty Museum said Thursday it plans to return to Sicily a terra-cotta head depicting the Greek god Hades after determining it was clandestinely excavated from an archaeological site in the 1970s.

The museum took the initiative to investigate the piece's origins after seeing fragments in a publication that could join to the head, which dates to about 300 or 400 B.C., according to Timothy Potts, the museum's director.

The Getty acquired the piece in 1985, and Potts said it's believed it was taken from the Morgantina Archaeological Park in Italy in the 1970s.

The original location of the head was the site of the sanctuary of Demeter, the Greek goddess of the harvest, whose daughter Persephone was married to Hades.

The Getty purchased the piece from New York collector Maurice Tempelsman. It is among more than 40 pieces the museum has returned to Greece and Italy in recent years.

The terra-cotta body of Hades is undergoing an extensive restoration at the Museo Archeologico in the Italian city of Aidone.

The head will be on view at the Getty Villa from April 3 to Aug. 19. It then travels to the Cleveland Museum of Art for display from fall until January 2014 before appearing in February at the Palazzo Ajutamicristo in Palermo, Italy.