Separating about two thousand Celts from the others and dividing them into three bodies, he put each under the charge of two of the young men who were managing the affair, sending also some of his own officers to accompany them with orders to occupy the most convenient approaches to the market;
and when they had done this he ordered the Tarentine young men to set apart and save any of the citizens they met and to shout from a distance advising all Tarentines to stay where they were, as their safety was assured.
At the same time he ordered the Carthaginian and Celtic officers to put all Romans they met to the sword. The different bodies hereupon separated and began to execute his orders.
As soon as it was evident to the Tarentines that the enemy were within the walls, the city was filled with clamour and extraordinary confusion.
When Gaius heard of the entrance of the enemy, recognizing that his drunken condition rendered him incapable, he issued from his house with his servants and made for the gate that leads to the harbour, where as soon as the guard there had opened the postern for him, he escaped through it, and getting hold of one of the boats at anchor there embarked on it with his household and crossed to the citadel.
Meanwhile Philemenus and his companions, who had provided themselves with some Roman bugles and some men who had learnt to sound them, stood in the theatre and gave the call to arms.
The Romans responding in arms to the summons and running, as was their custom, towards the citadel, things fell out as the Carthaginians designed.
For reaching the thoroughfares in disorder and in scattered groups, some of them fell among the Carthaginians and some among the Celts, and in this way large numbers of them were slain.
When day broke the Tarentines kept quietly at home unable as they were yet to understand definitely what was happening.
For owing to the bugle call and the fact that no acts of violence or pillage were being committed in the town they thought that the commotion was due to the Romans;
but when they saw many Romans lying dead in the streets and some of the Gauls despoiling Roman corpses, a suspicion entered their minds that the Carthaginians were in the town.
Walbank Commentary