Petraeus says he is shocked to learn of harassing emails sent by mistress

Former CIA Director David Petraeus told the Associated Press Monday that he was shocked to learn of the harassing emails his mistress sent that spurred an FBI investigation, according to the Star Tribune.

Petraeus stepped down from his position Friday, according to the Star Tribune. His resignation followed an FBI investigation into a supposed extramarital affair he was having, the Star Tribune says.

The New York times said that the FBI was prompted to begin an investigation after Jill Kelley, a friend of Petraeus, reported receiving anonymous harassing emails ordering her to stay away from Petraeus.

The emails were traced back to Paula Broadwell, Petraeus' biographer, according to the New York Times.