On April 24, 1960, Gilbert R. Mason, Sr., M.D., led about 125 volunteers in a peaceful wade-in on segregated Biloxi Beach. Trained in non-violent passive resistance, they expected to be arrested. Instead they were attacked by a white mob armed with pipes, chains, and lumber, while city police stood by without intervening. In May the U.S. Justice Department sued the city for denying blacks the use of the beach. Eight years later it won its case, and the beaches were legally opened to all races. After returning to Mississippi in 1955 to practice medicine in Biloxi, Mason sought to challenge Jim Crow restrictions and secure African American access to Harrison County's twenty-six-mile taxpayer-funded beach. In May 1959 he led nine people onto the public beach near the old Biloxi cemetery, where police ordered them off and threatened arrest, beginning Mississippi's first non-violent civil disobedience campaign. In June, Mason and Dr. Felix Dunn organized the Harrison County Civic Action Committee and revived the Biloxi Civic League. After a petition to the Harrison County Board of Supervisors in October 1959 was met with hostility and threats of bloodshed, Mason returned alone for a wade-in on April 17, 1960, and was arrested. A week later, after volunteers had been coached in nonviolent tactics and Dunn had notified the sheriff, Mason and 125 others entered the water and were assaulted by a large white mob carrying bricks, pipes, baseball bats, and chains while sheriff's deputies, including the sheriff, did nothing to stop it. Mason delayed his own arrest so he could tend the wounded. The press called the event the bloody wade-in, its violence sparked local riots in which two young black men were murdered, and it led to boycotts, voter registration drives, and a Biloxi branch of the NAACP with Mason as president. The Civil Rights Division of the U.S. Justice Department then filed the first federal challenge to Mississippi's Jim Crow laws against Harrison County officials and Biloxi authorities, and on August 16, 1968, Judge J. P. Coleman issued the opinion that opened the beaches.