History of the Peloponnesian War

And this success had they that entered into Plataea.

But the rest of the Thebans that should with their whole power have been there before day for fear the surprise should not succeed with those that were in, came so late with their aid that they heard the news of what was done by the way.

Now Plataea is from Thebes seventy furlongs, and they marched the slower for the rain which had fallen the same night. For the river Asopus was swollen so high that it was not easily passable.

So that what by the foulness of the way and what by the difficulty of passing the river, they arrived not till their men were already some slain and some taken prisoners.

When the Thebans understood how things had gone, they lay in wait for such of the Plataeans as were without (for there were abroad in the villages both men and household stuff, as was not unlikely, the evil happening unexpectedly and in time of peace), desiring, if they could take any prisoners, to keep them for exchange for those of theirs within, which (if any were so) were saved alive.