The Messenger of Allah ﷺ said, "Injustice will be darknesses on the Day of Resurrection."
قال رسول الله ﷺ: إن الظلم ظلمات يوم القيامة.
Bukhari narrated it in the Book of Injustices (2447), and Muslim in the Book of Virtue and Kinship Ties (2579), both from the hadith of Abdul-Aziz bin Majishun, from Abdullah bin Dinar, from Ibn Umar, and he mentioned it.