There were also discriminatory immigration laws against Asian immigrants. The Chinese Exclusion Act banned Chinese immigration and denied Chinese residents the right to citizenship. Angel Island Immigration Station detained Asian immigrants for generally two weeks to six months before allowing them to enter the United States. Laws in 1917 and 1924 placed literacy tests on immigrants and established the Asiatic Barred Zone restricting immigration from parts of Asia, nearly excluding all Asians from entering the U.S.