Psalm 106:37-38 "They even sacrificed their sons and their daughters to the demons, and shed innocent blood, the blood of their sons and their daughters, whom they sacrificed to the idols of Canaan; and the land was polluted with the blood."
Gen 4:8-11
Then the Lord said to Cain, “Where is Abel your brother?” He said, “I do not know. Am I my brother’s keeper?” And He said, “What have you done? The voice of your brother’s blood cries out to Me from the ground. So now you are cursed from the earth, which has opened its mouth to receive your brother’s blood from your hand.”
God will avenge the blood of these innocents.