Passage 7.11.6
χρόνος τε δὴ οὐ πολὺς ὁ μεταξὺ ἤνυστο, καὶ τῶν φρουρῶν ἀδικοῦσιν ἄνδρες Ὠρωπίους. οἱ μὲν δὴ ἐς τὰς Ἀθήνας ἀπέστελλον ὁμήρους τε ἀπαιτήσοντας καὶ φρουράν σφισιν ἐξάγειν κατὰ τὰ συγκείμενα ἐροῦντας· Ἀθηναῖοι δὲ οὐδέτερα ἔφασαν ποιήσειν, ἀνθρώπων γὰρ τῶν ἐπὶ τῇ φρουρᾷ καὶ οὐ τοῦ Ἀθηναίων δήμου τὸ ἁμάρτημα εἶναι· τοὺς μέντοι αὐτὰ εἰργασμένους ἐπηγγέλλοντο ὑφέξειν δίκην.
Indeed, not much time passed before the guards wronged certain men of Oropus. The Oropians therefore sent envoys to Athens, demanding hostages and requesting that the garrison be withdrawn in accordance with the agreement. But the Athenians refused to do either, saying the wrongdoing was the fault of the men serving as guards, and not of the Athenian people as a whole; nevertheless, they promised to bring those responsible to justice.