Tresckow worked tirelessly to persuade army commanders such as Field Marshals Fedor von Bock, Günther von Kluge and Erich von Manstein to join in the conspiracy without much success. With unwitting help from Schmundt, he placed like-minded officers as their adjutants and staff officers to bring them closer to the conspiracy. Kluge sympathised with the conspirators and at times seemed ready to act, only to become indecisive at critical moments. Others refused outright, Manstein declaring, "Prussian field marshals do not mutiny." Nonetheless, no-one reported their treasonable activities to the SS.