But Falkenhayn made no further progress that day. In the neighboring passes he was held back successfully while his left flank in the Oitoz Pass and his right flank in the Vulkan Pass were each thrown back. All during the 15th and the 16th the fighting in the passes continued desperately, the battle being especially obstinate before the railroad terminus at Campulung, up in the foothills. At about this same time the Russians in the Dorna Vatra district, where they joined with the Rumanians, began a strong offensive, in the hope of relieving the pressure on the Rumanians farther down. This attempt was hardly successful, as the German opposition in this sector developed to unexpected strength. On the 17th Falkenhayn succeeded in squeezing himself through Gyimes Pass and reaching Agas, seven miles inside the frontier. At about the same time strong fighting began in the Red Tower Pass. The battle was, indeed, raging at a tense heat up and down the whole front. It was now becoming obvious that the Central Powers had determined to make an example of Rumania and punish her "treachery," as they called it, even though they must suspend activity in every other theater of the war to do so. Not a little anxiety was caused in the Allied countries. The matter was brought up and caused a hot discussion in the British Parliament. In the third week France sent a military mission to Bucharest under General Berthelot, while England, France, and Russia were all making every effort to keep the Rumanians supplied with ammunition, in which, however, they could not have been entirely successful.
The Rumanians, on their part, continued defending every step forward made by the enemy. On the 18th they won a victory in the Gyimes Pass which cost the enemy nearly a thousand prisoners and twelve guns. At Agas, in the Oitoz region, the Austro-Germans also suffered a local defeat. Nor had they so far made very marked progress in the passes behind Brasso. There seems to be no doubt that had the Rumanians been able to devote all their forces and resources to the defense of the Hungarian frontier, they would probably have been able to hold back Falkenhayn's forces. But Mackensen had forced them to split their strength.