(Bloomberg) — Three descendants of Holocaust victims sued the French national railroad over claims it was paid to confiscate property and transport Jews and others to Nazi concentration camps.

Relatives of the three were on their way to Auschwitz and Buchenwald when their property, including gold, money and other personal belongings, were taken by the Societe Nationale des Chemins de Fer, or SNCF, according to the complaint filed Thursday in federal court in Chicago.

During World War II SNCF was paid to help with Nazi deportations, according to the complaint. SNCF assembled and ran deportation trains that took 75,000 Jews of all nationalities to the camps in 72 convoys, the three plaintiffs said.

SNCF is accused in the complaint of violations of international law, conversion of the allegedly stolen property for profit and unjust enrichment.

The plaintiffs are Karen Scalin, who lives in Illinois, and French residents Josiane Piquard and Roland Cherrier. They seek class certification to represent others who were transported to Nazi camps by SNCF or their descendants. They also seek disgorgement of revenues allegedly earned from confiscated property.

SNCF representatives didn’t immediately respond to e-mail messages after regular business hours Thursday seeking comment on the lawsuit.