A passenger train travelling Traveling from Oran to the capital Algiers and consisting Containing of a locomotive and eight carriages stalled on a steep gradient leading to a mountain pass a few kilometres beyond the town of Bouhalouane in the Chlef Province of Algeria .

The coup Change_of_leadership was to come in two phases : an assertion of control Control in French Algeria 's major cities Algiers , Oran and Constantine .

The commanders in Oran and Constantine , however , refused Agree_or_refuse_to_act to follow Challe 's demand Request that they join Becoming_a_member the coup Change_of_leadership .