Srimad-Bhagavatam: Canto 11 - Chapter 1 - Verse 19
Sanskrit:
पुत्रा अयुध्यन् पितृभिर्भ्रातृभिश्चस्वस्रीयदौहित्रपितृव्यमातुलै: ।मित्राणि मित्रै: सुहृद: सुहृद्भि-र्ज्ञातींस्त्वहन् ज्ञातय एव मूढा: ॥ १९ ॥
ITRANS:
putrā ayudhyan pitṛbhir bhrātṛbhiś casvasrīya-dauhitra-pitṛvya-mātulaiḥmitrāṇi mitraiḥ suhṛdaḥ suhṛdbhirjñātīṁs tv ahan jñātaya eva mūḍhāḥ
Translation:
Thus bewildered, sons fought with fathers, brothers with brothers, nephews with paternal and maternal uncles, and grandsons with grandfathers. Friends fought with friends, and well-wishers with well-wishers. In this way intimate friends and relatives all killed one another.