A police officer was fatally shot and a man was killed when drug investigators raided a home in the rural Yolo County community of Madison. Officer Jim McKnight, 39, who died of a head wound at a Sacramento hospital, was the first West Sacramento officer killed in the line of duty since the city's incorporation two years ago. Police said Luis Orosco, 41, described by relatives as mentally handicapped, was killed after he barricaded himself in a back bedroom and shot it out with officers. No drugs were found in the home, one of four raided simultaneously. At two other locations, officers arrested six people, confiscated firearms and seized about a pound of cocaine.