Pickaway County Sheriff's deputies have now issued an arrest warrant for a man in Thursday's shaken-baby syndrome death of a ten-month-old boy.Deputies had described 44-year-old Wayne Walker, the boyfriend of the child's mother, as a person of interest in the case. Deputies have now filed a murder charge against Walker, who remains at-large. The mother, 24-year-old Elizabeth Rutter of Laurelville, has not been charged.