NEW YORK — A retired New York City school librarian has been sentenced to 15 years in prison for scheming to carry out gruesome fantasies of kidnapping, torturing and killing women and girls.

Robert Christopher Asch was sentenced Monday in Manhattan federal court.

The 65-year-old Manhattan resident was convicted in March 2014 along with a New Jersey auto mechanic.

Prosecutors said Asch conspired from the spring of 2011 to January 2013 to kidnap, torture and kill the wife of a co-defendant and a female FBI agent working undercover. No one was hurt.

The convictions came a year after the headline-grabbing case of a police officer accused of plotting abductions and cannibalism.

A judge tossed the most serious charges after that trial and sentenced the ex-officer to time served for a misdemeanor.