An-Nisa 4:92

Wama kana limu/minin anyaqtula mu/minan illa khataan waman qatala mu/minankhataan fatahreeru raqabatin mu/minatin wadiyatunmusallamatun ila ahlihi illa an yassaddaqoofa-in kana min qawmin AAaduwwin lakum wahuwa mu/minun fatahreeruraqabatin mu/minatin wa-in kana min qawmin baynakumwabaynahum meethaqun fadiyatun musallamatun ilaahlihi watahreeru raqabatin mu/minatin faman lam yajid fasiyamushahrayni mutatabiAAayni tawbatan mina Allahi wakanaAllahu AAaleeman hakeema

And never is it for a believer to kill a believer except by mistake. And whoever kills a believer by mistake - then the freeing of a believing slave and a compensation payment [diyah] presented to his [i.e., the deceased's] family [is required], unless they give [up their right as] charity. But if he [i.e., the deceased] was from a people at war with you and he was a believer - then [only] the freeing of a believing slave; and if he was from a people with whom you have a treaty - then a compensation payment presented to his family and the freeing of a believing slave. And whoever does not find [one or cannot afford to buy one] - then [instead], a fast for two months consecutively, [seeking] acceptance of repentance from Allāh. And Allāh is ever Knowing and Wise.

It is not for a believer (Muslim) to kill any believer, except by mistake. Whoever kills a believer by mistake, then, a believing slave has to be freed, and the blood money must be paid to his family, unless they forgo it.If he (the victim) belongs to a people hostile to you and is a believer, then, a believing slave has to be freed. If he (the victim) belongs to a people between whom and you there is treaty, then, blood money is to be paid to his family, and a believing slave to be freed. Whoever does not find one has to fast for two consecutive months. This is repentance prescribed from Allah’s side. Allah is All-Knowing, All-Wise.