The thinly staffed colonial administration provided only weak supervision over arid Kanem Prefecture and the sparsely populated areas of Guéra and Salamat prefectures. Old-fashioned razzias continued in the 1920s, and it was reported in 1923 that a group of Senegalese Muslims on their way to Mecca had been seized and sold into slavery. Unwilling to expend the resources required for effective administration, the French government responded with sporadic coercion and a growing reliance on indirect rule through the sultanates.