Catiline, accordingly, left the city at once with three hundred armed followers, assumed the fasces and axes as though he were a magistrate, raised standards, and marched to join Manlius; and since about twenty thousand men altogether had been collected, he marched round to the various cities endeavouring to persuade them to revolt, so that there was now open war, and Antonius was sent off to fight it out.
Edition :
Plutarch Lives VII: Demosthenes and Cicero, Alexander and Caesar, ed. E. H. Warmington, trans. Bernadotte Perrin (The Loeb Classical Library 99), Cambridge - London 1967 (first ed. 1919).
Notes :
Catilina tries to have Cicero killed (Plut., Cic., 16, 1f.) - afterwards Cicero ordered Catilina to leave Rome and therefore he joins his forces with Gaius Manlius to regain his strength.