Leclerc returned to his military duties with the Army of the Rhine, and was sent on an unsuccessful spy mission across the Rhine in southwest Germany. It seems that he betrayed by Dietrich, the mayor of Strasbourg. In November 1792, he fought at the Battle of Jemappes. In February 1793 he was transferred to the General Staff of the newly restructured Army of the Alps, in Lyon. It was there that he joined the "Club Central" and he was sent to Paris as a special deputy from Lyon.