A veteran CIA clandestine officer, who has spearheaded sensitive talks with Pakistan and Yemen, is retiring after a tumultuous career with the spy agency, according to media reports. CIA Deputy Director Stephen Kappes will step down in May, CIA Director Leon Panetta announced Wednesday. Panetta said he has asked Michael Morell, a 30-year veteran of the agency, to take the No. 2 post. Morell has been chief of the intelligence directorate and earlier the associate deputy director. Kappes, a stern former Marine who over his career served undercover in Moscow, Islamabad, and, in the 1980s, at a secret C.I.A. station in Germany collecting information about Iran, was the first officer from the clandestine service to become the agencys second-ranking official since the early 1980s. Kappes returned to the CIA in 2006. He had resigned in 2004 after disputes with then-director Porter Goss and his team.