On October 14, 1964, King won the Nobel Peace Prize for combating racial inequality through nonviolent resistance. In 1965, he helped organize the Selma to Montgomery marches. The following year, he and the SCLC took the movement north to Chicago to work on segregated housing. In his final years, he expanded his focus to include opposition towards poverty and the Vietnam War. He alienated many of his liberal allies with a 1967 speech titled "Beyond Vietnam". J. Edgar Hoover considered him a radical and made him an object of the FBI's COINTELPRO from 1963 on. FBI agents investigated him for possible communist ties, recorded his extramarital liaisons and reported on them to government officials, and on one occasion mailed King a threatening anonymous letter, which he interpreted as an attempt to make him commit suicide.