History of the Peloponnesian War
Thucydides
Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.
So he immediately sent a part of his army to forestall these troops by setting ambuscades along the roads and occupying the strong positions, and at the same time began preparations to lead the rest of the army against them.
In the meantime the Mantineans and the others who were included in the agreement, leaving camp on the pretext of gathering pot-herbs and firewood, stole away in small groups, gathering at the same time what they pretended to have gone to seek; then when they had already got some distance from Olpae they quickened their pace.
But the Ambraciots and all the others who happened to have come together in a body, when they realized that these were taking their departure, also set out themselves and ran at full speed, wishing to overtake them.[*](The text is most probably corrupt. Classen offers the best remedy: οἱ δὲ )αμπρακιῶται καὶ οἱ ἄλλοι ὅσοι μονούμενοι ἐτύγχανον οὕτως, ἀθρόοι ξυνελθόντες ὡς ἕγνωσαν ἀπιόντας, ὥρμησαν καὶ αὐτοὶ. . ·“But the Ambraciots and all the others who chanced to be left came together in a body, and when they realised that they were taking their departure set off also themselves . . .”)
But the Acarnanians at first thought that all the fugitives were going away without covenant or truce and therefore set off in pursuit of the Peloponnesians; and when some of the generals tried to prevent this, saying that a truce had been made with them, someone hurled javelins at them, believing that they had been betrayed. Afterwards, however, they let the Mantineans and Peloponnesians go, but began to kill the Ambraciots.