A Walmart manager opened fire on fellow employees in the break room of a Virginia store, killing six people in the country's second high-profile mass shooting in four days, police and a witness said Wednesday. The gunman, who apparently shot himself, was dead when police found him, Chesapeake Police Chief Mark G. Solesky said. There was no clear motive for the shooting, which also put four people in the hospital. An eyewitness described the chaotic scenes in the immediate aftermath of the shooting in a video obtained by the Associated Press.