Beginning in World War I, German Americans were sometimes accused of having political allegiances to Germany rather than the United States. The Justice Department attempted to prepare a list of all German aliens, counting approximately 480,000 of them, more than 4,000 of whom were imprisoned in 1917–18. The allegations included spying for Germany, or endorsing the German war effort. Thousands were forced to buy war bonds to show their loyalty. The Red Cross barred individuals with German last names from joining in fear of sabotage. One person was killed by a mob; in Collinsville, Illinois, German-born Robert Prager was dragged from jail as a suspected spy and lynched. Questions of German American loyalty increased due to events like the German bombing of Black Tom island and the U.S. entering World War I, many German Americans were arrested for refusing allegiance to the U.S. War hysteria led to the removal of German names in public, names of things such as streets, and businesses. Schools also began to eliminate or discourage the teaching of the German language. Years later during the Second World War, German Americans were once again the victims of war hysteria discrimination. Following its entry into the Second World War, the US Government interned at least 11,000 American citizens of German ancestry. The last to be released, a German-American, remained imprisoned at Ellis Island until 1948, three and a half years after the cessation of hostilities against Germany.