Despite the German retreat, neither Third nor Fourth Army made much progress. Joffre rebuked Sarrail over the telephone on 13 September 1914, demanding a formal inquiry of how Sarrail had "not been informed" of the enemy retreat 48 hours previously, a demand which Sarrail sidestepped by having his staff telephone a routine progress report to Joffre. To the south-east of Verdun the Germans took Fort Troyon on 13 September and Fort Camp des Romains on 26 September, creating the Saint-Mihiel Salient. The salient cut off one of the railway lines supplying Verdun, which would force the defenders to rely heavily on road transport in the 1916 battle.