God speaking through the prophet Jeremiah accuses the inhabitants of Jerusalem of shedding "innocent" blood to "Baal"
The innocent blood was in sacrificing their children (sons) to Baal.
Jer 19:4 Because they have forsaken me, and have estranged this place, and have burned incense in it unto other gods, whom neither they nor their fathers have known, nor the kings of Judah, and have filled this place with the blood of innocents;
Jer 19:5 They have built also the high places of Baal, to burn their sons with fire for burnt offerings unto Baal, which I commanded not, nor spake it, neither came it into my mind:
How do you link the blood of the innocents to the sons? By putting also in the sentence it makes two different things. The innocent could as well being people loyal to God. The sons good be 30.