Between 1850 and 1875, the most frequent complaint against Chinese residents was their involvement in prostitution. During this time, Hip Yee Tong, a secret society, imported over six-thousand Chinese women to serve as prostitutes. Most of these women came from southeastern China and were either kidnapped, purchased from poor families, or lured to ports like San Francisco with the promise of marriage. Prostitutes fell into three categories, namely, those sold to wealthy Chinese merchants as concubines, those purchased for high-class Chinese brothels catering exclusively to Chinese men, or those purchased for prostitution in lower-class establishments frequented by a mixed clientele. In late-19th century San Francisco, most notably Jackson Street, prostitutes were often housed in rooms 10×10 or 12×12 feet and were often beaten or tortured for not attracting enough business or refusing to work for any reason. In San Francisco, "highbinders" (various Chinese gangs) protected brothel owners, extorted weekly tributes from prostitutes and caused general mayhem in Chinatown. However, many of San Francisco's Chinatown whorehouses were located on property owned by high-ranking European-Americans city officials, who took a percentage of the proceeds in exchange for protection from prosecution. From the 1850s to the 1870s, California passed numerous acts to limit prostitution by all races, yet only Chinese were ever prosecuted under these laws. After the Thirteenth Amendment was passed in 1865, Chinese women brought to the United States for prostitution signed a contract so that their employers would avoid accusations of slavery. Many Americans believed that Chinese prostitutes were corrupting traditional morality, and thus the Page Act was passed in 1875, which placed restrictions on female Chinese immigration. Those who supported the Page Act were attempting to protect American family values, while those who opposed the Act were concerned that it might hinder the efficiency of the cheap labor provided by Chinese males.