After the war in Europe started, he was a member of the mobile SS death squad, Einsatzgruppen IV in Poland through 1940.

Later he was promoted to the rank of SS-Hauptsturmführer and served in the SS-Sicherheitsdienst (SD; Security Service) in Libya and Tunisia between 1942 and 1943, under Walter Rauff.

[1] After the war, in 1962, while a Kriminalrat at Sicherungsgruppe Bonn, he led a police raid on the Spiegel scandal.

A group of historians therefore concluded, he was under protection of American intelligence service by then (T. Naftali: The CIA and Eichmann's Associates.

Protected through his connections in post-war Germany, Saevecke was sentenced in absentia in Turin in 1999 to life imprisonment for his involvement in the execution of hostages in Milan in August 1944 but never extradited to Italy.