KANISHKA SINGH SIX people including a six-month-old baby cradled in the arms of her 17-year-old mother were shot dead at a home in California's main agricultural valley in what authorities called a targeted attack and "horrific massacre." Tulare County Sheriff Mike Boudreaux linked the killings to the illegal drug trade, saying deputies had conducted a drug-related search warrant at the same home last week. "We believe this was a message being sent," Boudreaux told reporters at the scene. "We believe that this was a targeted family." Two suspects remained at large, he said. Authorities responded early on Monday after multiple…