Police: 2 children stabbed to death, nanny arrested

By Shimon Prokupecz, NBCNewYork.com NEW YORK CITY -- Two children have died after they were found stabbed along with at least two other adults inside an Upper West Side home, a law enforcement source says.  Police had responded to a 911 call of several people, including adults and and two children, found stabbed in the home. Emergency responders were on the scene in front of 57 W. 75th St., just a block from Central Park and two blocks from the Museum of Natural History.  View complete coverage from NBCNewYork.com A suspect is in custody, according to a law enforcement official. Businesses had been told to close their doors earlier as police swarmed the area. Traffic around Columbus Avenue and 75th Street is heavily backed up. Check back for updates on this developing story.