The Massacre at Bloody Falls was an incident that took place during Samuel Hearne's exploration of the Coppermine River on the 17 July 1771. Chipewyan and "Copper Indian" Dene men led by Hearne's guide and companion Matonabbee attacked a group of Copper Inuit camped by rapids approximately 15 km (9.3 mi) upstream from the mouth of the Coppermine River. Just after midnight on 17 July, the Dene set upon the Inuit camp and killed approximately 20 men, women, and children.