A Lancaster, California, man has been arrested for allegedly killing and decapitating his son and daughter, police said. Firefighters initially responded to a possible gas leak at the house in the 45000 block of Century Circle after 7:30 a.m. Friday. Upon entering, they discovered the bodies of a 12-year-boy and 13-year-old girl, the Los Angeles County Sheriff’s Department said in a news release. L.A....