Without loss of time Almeric de Clisson issued forth from the great gate of Hennebon, accompanied by 300 men-at-arms and 1,000 archers. The latter took post at once along the edge of the ditches. The men-at-arms rode straight for the enemy's camp, which was undefended, the whole army being within their tents at dinner. Dashing into their midst the English and Breton men-at-arms began to overthrow the tents and to spear all that were in them. Not knowing the extent of the danger or the smallness of the attacking force, the French knights sprang up from table, mounted, and rode to encounter the assailants. For some time these maintained their ground against all assaults until, finding that the whole army was upon them, Almeric de Clisson gave order for his troop to retire slowly upon the town. Fighting every step of the ground and resisting obstinately the repeated onslaught of the French, Clisson approached the gate. Here he was joined by the archers, who with bent bows prepared to resist the advance of the French. As it now appeared that the garrison were prepared to give battle outside the walls, the whole French army prepared to move against them. In the mean time Sir Walter Manny, with 100 men-at-arms and 500 horse archers, issued by a sally-port on the other side of the town, and with all speed rode round to the rear of the French camp. There he found none to oppose him save servants and camp-followers, and making his way straight to the tent of Charles of Blois, where the two knights were confined, he soon freed them from their bonds. They were mounted without wasting a moment's time upon two spare horses, and turning again the whole party rode back toward Hennebon, and had reached the postern gate before the fugitives from the camp reached the French commanders and told them what had happened. Seeing that he was now too late, because of De Clisson's sortie, Charles of Blois recalled his army from the attack, in which he could only have suffered heavily from the arrows of the archers and the missiles from the walls. The same day, he learned from some prisoners captured in the sortie, of the undiminished spirit of the garrison, and that Hennebon was amply supplied by provisions brought by sea. His own army was becoming straitened by the scarcity of supplies in the country round; he therefore determined at once to raise the siege, and to besiege some place where he would encounter less serious resistance. Accordingly next morning he drew off his army and marched to Carhaix.