It was narrated from Ibn 'Abbas, who attributed it to the Prophet ﷺ:
“Whoever kills out of folly or for tribal motives, using a rock, a whip, or a stick; he must pay the blood money for killing by mistake. Whoever kills deliberately, he is to be killed in retaliation. Whoever tries to prevent that, upon him is the curse of Allah, the angels and all the people, and no change nor equitable exchange will be accepted from him.”

حَدَّثَنَا مُحَمَّدُ بْنُ مَعْمَرٍ، حَدَّثَنَا مُحَمَّدُ بْنُ كَثِيرٍ، حَدَّثَنَا سُلَيْمَانُ بْنُ كَثِيرٍ، عَنْ عَمْرِو بْنِ دِينَارٍ، عَنْ طَاوُسٍ، عَنِ ابْنِ عَبَّاسٍ، رَفَعَهُ إِلَى النَّبِيِّ ﷺ قَالَ " مَنْ قَتَلَ فِي عِمِّيَّةٍ أَوْ عَصَبِيَّةٍ بِحَجَرٍ أَوْ سَوْطٍ أَوْ عَصًا فَعَلَيْهِ عَقْلُ الْخَطَإِ وَمَنْ قَتَلَ عَمْدًا فَهُوَ قَوَدٌ وَمَنْ حَالَ بَيْنَهُ وَبَيْنَهُ فَعَلَيْهِ لَعْنَةُ اللَّهِ وَالْمَلاَئِكَةِ وَالنَّاسِ أَجْمَعِينَ لاَ يُقْبَلُ مِنْهُ صَرْفٌ وَلاَ عَدْلٌ " .