On October 24, 1871, a mob estimated at approximately 500 white and Latino Americans attacked, robbed, and killed Chinese immigrant residents of Los Angeles in the neighborhood then known as Calle de los Negros, or "Negro Alley," in what is today referred to as the old Chinatown district. The violence followed a chain of events rooted in a feud between rival Chinese associations, the Hong Chow and Nin Yung companies, over the alleged abduction of a woman named Yut Ho. On the afternoon of October 24, gunfire during a related confrontation on Negro Alley left a Chinese man, Won Choy, fatally wounded in the neck. Police Constable Jesus Bilderrain responded and was shot while attempting to make an arrest inside the Coronel Adobe building. A civilian, farmer Robert Thompson, was also shot while assisting police and died roughly two hours later at an apothecary.
News of Thompson's death, combined with rumors that Chinese residents "were killing whites wholesale," drew a large crowd to the boundaries of Negro Alley. The mob besieged the Coronel Adobe, firing into the building, cutting holes in its roof with axes, and dragging occupants outside. Chinese residents were hanged at three locations near downtown Los Angeles: from the awning of a carriage shop, from wagons parked nearby, and from the gate of a lumberyard. Of the 19 Chinese immigrants killed, 15 were hanged by the mob; the others died from gunshots at the Coronel Adobe. At least one victim was mutilated, his finger cut off to remove a diamond ring. The dead represented more than 10 percent of the roughly 172 Chinese residents of Los Angeles at the time. The mob also ransacked nearly every Chinese-occupied building on the block.
A coroner's inquest and grand jury investigation followed, producing 49 indictments naming approximately 150 individuals. Ten men were ultimately prosecuted. In People v. Kerren, a constable was acquitted of assault charges. In People v. Ah Shaw, et al., two Chinese defendants were acquitted for lack of evidence in the killing of Won Choy. In the combined trials stemming from the death of Dr. Chee Long "Gene" Tong, eight men — Esteban Alvarado, Charles Austin, Refugio Botello, L. F. Crenshaw, A. R. Johnson, Jesus Martinez, Patrick M. McDonald, and Louis Mendel — were convicted of manslaughter and sentenced to two to six years at San Quentin State Prison. On May 21, 1873, the California Supreme Court overturned these convictions, ruling the indictment had failed to properly allege that Gene Tong had been murdered. District Attorney Cameron E. Thom declined to retry the cases, and the men were freed in spring 1873. Sam Yuen, a merchant accused of aiding an attack on police, was acquitted at trial in November 1872. A separate civil suit brought by Chinese merchants against the city for property damage was rejected by the courts.
The massacre drew national attention and was reported by East Coast newspapers, which described Los Angeles as a "blood stained Eden." Calle de los Negros was later renamed and absorbed into Los Angeles Street, and the Coronel Adobe was demolished in the late 1880s.