LXX 2 Macc 5:6

ὁ δὲ Ἰάσων ἐποιεῖτο σφαγὰς τῆς πόλεως τῶν ἰδίων ἀφειδῶς, οὐ συννοῶν τὴν εἰς τοὺς συγγενεῖς εὐημερίαν δυσημερίαν εἶναι τὴν μεγίστην, δοκῶν δὲ πολεμίων καὶ οὐχ ὁμοεθνῶν τρόπαια καταβάλλεσθαι.

But Jason slew his countrymen without mercy, not considering that prosperity against one's own kindred is a very great evil, thinking they had been enemies, and not citizens, whom he conquered.