NEW CITY (AP) — The Rockland County Sheriff's Office is investigating after a police K-9 killed a family's dog in an unprovoked attack in New York.Police say the attack happened in New City around 7 a.m. Tuesday. Tom Forde tells WCBS-TV a nanny was walking his family's Cavapoo when the police dog attacked it.Authorities say Detective Dwayne Defino was able to get the German shepherd off of the smaller dog.