History of the Peloponnesian War

In the end, when many dead lay heaped in the river, and the army was utterly defeated, part at the river, and part (if any gat away) by the horsemen, Nicias yielded himself unto Gylippus (having more confidence in him than in the Syracusians) to be for his own person at the discretion of him and the Lacedaemonians, and no further slaughter to be made of the soldiers.

Gylippus from thenceforth commanded to take prisoners. So the residue, except such as were hidden from them (which were many), they carried alive into the city. They sent also to pursue the three hundred which brake through their guards in the night, and took them.

That which was left together of this army to the public was not much; but they that were conveyed away by stealth were very many;

and all Sicily was filled with them, because they were not taken, as those with Demosthenes were, by composition. Besides, a great part [of these] were slain; for the slaughter [at this time] was exceeding great, none greater in all the Sicilian war. They were also not a few that died in those other assaults in their march. Nevertheless, many also escaped, some then presently and some by running away after servitude; the rendezvous of whom was Catana.