TALLAHASSEE, Fla. - A 474-year-old painting plundered by the Nazis during World War Two was turned over on Wednesday to the heirs of its Italian Jewish owner, ending a 15-year international effort to restore the work to its rightful owners.Flanked by representatives from Interpol and the US Attorney's office, US Homeland Security Investigations Special Agent Susan McCormick outlined the events leading to the return of "Christ Carrying the Cross Dragged By A Rascal" by Italian artist Girolamo de' Romani.The painting, stolen during the Nazi occupation of France, has been under the protection of the US government since November."Seventy years is a very long time," McCormick told reporters. "But it shows that it is never too late to right a wrong."The piece was one of 70 items stolen from the collection of Frederico Gentili di Giuseppe, an Italian Jew who had lived in Paris. He died of natural causes in 1940, a month before the Nazis invaded France, and his children and grandchildren had already fled the country.The collection was sold by the French Vichy government in 1941 and Gentili's grandchildren filed suit in 1997 to get it back.The painting, which depicts Christ crowned in thorns, carrying a cross and dressed in a copper-colored silk robe, dates back to circa 1538. It was one of more than 50 pieces on loan from the Pinacoteca di Brera museum in Milan, Italy, to the Mary Brogan Museum of Art and Science in Tallahassee, Florida.Based on a tip from an employee of Christie's auction house in June 2011, Interpol investigators last summer alerted US officials that the painting may have been stolen.In November, US officials confiscated the work as investigations continued on both sides of the Atlantic.The piece is one of hundreds of thousands of works of art stolen from Jewish families throughout Europe by the Nazis. It is among nearly 2,500 works of art and antiquities that Homeland Security Investigations officials have repatriated to 23 countries since 2007.Gentili's grandson, Lionel Salem, told reporters by telephone on Wednesday the six heirs plan to sell the work, which he said is to be auctioned at Christie's in New York on June 6. The painting has been insured for $2.5 million."For a cake, it is relatively easy cutting it into six, not totally easy but quite easily," Salem said of the family's decision to sell. "But for a painting, you see, it is more difficult."