Hadithcore
Hadith #2114510

Ibn ’Umar (RAA) narrated, ‘A young boy was murdered deceitfully. 'Umar (RAA) thereupon said, ‘If all the people of San'a’ (in Yemen) participated in killing him, I would kill them all.’ Related by al-Bukhari.

وَعَنْ اِبْنِ عُمَرَ رَضِيَ اَللَّهُ عَنْهُمَا قَالَ: { قُتِلَ غُلَامٌ غِيلَةً, فَقَالَ عُمَرُ: لَوْ اِشْتَرَكَ فِيهِ أَهْلُ صَنْعَاءَ لَقَتَلْتُهُمْ بِهِ } .‏ أَخْرَجَهُ اَلْبُخَارِيُّ [1]‏

References2 variants
Sunnah.com reference
Book 9, Hadith 17
Arabic/English book reference
Book 9, Hadith 1215