Neighbors of a 23-year-old man accused of fatally stabbing a woman with a 10-inch hunting knife during a rampage inside Winchester Public Library today say his behavior has been increasingly erratic in recent months and one even said he warned authorities that he “will kill somebody.” “We warned them. We warned them. I can’t believe this,” one of Jeffrey Yao’s neighbors told the Herald. “This whole thing could have been avoided, all of it.” The neighbor, who asked not to be identified out of fear of retribution, said Yao, identified by authorities as the man who fatally stabbed a 22-year-old...