Sunan an-Nasa'i, Book 45, Hadith 88 (In-Book) ⓘ
It was narrated from Abdullah bin 'Amr that the prophet said: "Indeed the accidental killing, which seems intentional, with a whip or a stick, (the Diyah) is one hundred camels, of which forty should be (she-camels) with their young in their wombs."
أَخْبَرَنِي يَحْيَى بْنُ حَبِيبِ بْنِ عَرَبِيٍّ، قَالَ أَنْبَأَنَا حَمَّادٌ، عَنْ خَالِدٍ، - يَعْنِي الْحَذَّاءَ - عَنِ الْقَاسِمِ بْنِ رَبِيعَةَ، عَنْ عُقْبَةَ بْنِ أَوْسٍ، عَنْ عَبْدِ اللَّهِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " أَلاَ وَإِنَّ قَتِيلَ الْخَطَإِ شِبْهِ الْعَمْدِ مَا كَانَ بِالسَّوْطِ وَالْعَصَا مِائَةٌ مِنَ الإِبِلِ أَرْبَعُونَ فِي بُطُونِهَا أَوْلاَدُهَا " .
also referenced under: Hadith 4793 (Reference) & Volume 5, Book 45, Hadith 4797 (DarusSalam)