IV Maccabees 15:20

20 When thou didst see children's flesh heaped upon children's flesh that had been torn off, heads decapitated upon heads, dead falling upon the dead, and a choir of children turned through torture into a burying ground, thou lamentedst not.

IV Maccabees 15:20 In-Context

18 Thy first-born, expiring, turned thee not; nor the second, looking miserable in his torments; nor the third, breathing out his soul.
19 Nor when thou didst behold the eyes of each of them looking sternly upon their tortures, and their nostrils foreboding death, didst thou weep!
20 When thou didst see children's flesh heaped upon children's flesh that had been torn off, heads decapitated upon heads, dead falling upon the dead, and a choir of children turned through torture into a burying ground, thou lamentedst not.
21 Not so do siren melodies, or songs of swans, attract the hearers to listening, O voices of children calling upon your mother in the midst of torments!
22 With what and what manner of torments was the mother herself tortured, as her sons were undergoing the wheel and the fires!

The Brenton translation of the Septuagint is in the public domain.