sentences:  In late May 1921, Silvestre had his first inking of trouble as he received reports that his supply columns he was sending up into the Riff mountains were regularly being destroyed.As Silvestre had pushed his men very deep into the Riff mountains and his forts and "blocaos" held little in the way of food, these ambushes threatened to bring down the entire chain that Silvestre had built.On 29 May 1921, Silvestre wrote to Bergenguer saying for the first time that the campaign against Krim might be more than a "mere kick in the pants" and that he needed more troops fast.