Titus Livius (Livy), The History of Rome, Book 40
Evan T. Sage, Ph.D. and Alfred C. Schlesinger, Ph.D., Ed.

25. While this was going on in Macedonia, Lucius Aemilius Paulus, whose imperium had been prolonged after his consulship, in the beginning of spring led the army against the Ligurian Ingauni. [2] [p. 79]As soon as he had encamped in the enemy's country,¹ ambassadors came to him to spy, although under the guise of seeking peace. [3] When Paulus said that he did not negotiate for peace except with people who had surrendered, they did not so much refuse to negotiate as say that they needed time to persuade a rude agricultural tribe. [4] When a truce for ten days was granted for this purpose, they then asked that the soldiers should not cross the mountains nearest the camp in quest of forage and wood: these, they said, were the cultivated parts of their territory. [5] When they obtained this, they massed their whole army under cover of those very mountains from which they had kept the enemy, and suddenly with a vest host advanced to attack the Roman camp at all the gates at once. [6] They continued the attack all day with the greatest violence, so that the Romans did not even have the opportunity to carry forth their standards nor any room to develop their line of battle. [7] Having been packed in the gates, they defended the camp more by blocking the entrances than by fighting. When the enemy had retired at sunset, Paulus sent two troopers to Gnaeus Baebius the proconsul at Pisa, with dispatches to the effect that he had been besieged during a truce and that Baebius should come to his aid as soon as possible. [8] Baebius had turned his army over to Marcus Pinarius the praetor, who was going to Sardinia: [9] but he informed the senate by letter that Lucius Aemilius was besieged by the Ligurians, and he wrote to Marcus Claudius Marcellus, whose province was nearest to them, that if it seemed wise to him he should march his army from Gaul against the Ligurians and rescue Lucius Aemilius from siege. [10] All these relief [p. 81]measures were destined to be late. The Ligurians² returned the next day to the camp. Although Aemilius had known that they would come and could have drawn his forces out into battle-line, he held his men within the rampart, so as to drag things out until Baebius and his army could arrive from Pisa.