This was the case of Ismail Bey, a major in "Istanbul's" army, and Selim Bey, the brigadier of the Guardia Regiments in the "Egyptian" army. When he found out that his brother was serving in the "enemy's" army, Ismail switched sides and joined the Pasha's forces … Equally interesting is the fact that most of the spy and reconnaissance reports in northern Syria were carried out by officers who were familiar with the region and who had previously been in the Sultan's service

Khaled Fahmy, All the Pasha_s Men_ Mehmed…, loc. 1437