BOULDER, Colo. (AP) – Police have closed their investigation into whether several female students at the University of Colorado were drugged at parties because of a problem with blood samples taken from some of the alleged victims. Blood samples were taken from three of the six women who believed they were drugged on Oct. 17 at four fraternities near the school’s campus in Boulder. Police later obtained the samples but they contained a “gel clot activator” that interfered with the testing equipment.