It was narrated from Abdullah bin 'Amr that the Prophet (ﷺ) said:
"Killing by mistake that resembles intentionally, is killing with a whip or stick, for which the blood money is one hundred camels, of which forty should be pregnant she-camels in middle of their pregnancies, with their young in their wombs." (TR)
English reference (TR): Vol. 3, Book 21, Hadith 2627 (TR)
Arabic reference (TR): Book 21, Hadith 2728 (TR)