May Allah curse the one who sees an oppressed and does not help him
Hadith No: 1
Al-Suyuti - al-Jami' al-Saghir wa Ziyadatuh - 10163 Volume: (1) - Page Number: (10163) 10163 - "May Allah curse whoever sees an oppressed person and does not support them."
Hadith No: 2
Al-Mutaqi al-Hindi - Kanz al-‘Ummal fi Sunan al-Aqwal wal-Af'al Volume: (3) - Page Number: (414) 7207 - "May Allah curse the one who sees an oppressed person and does not support him."