מדרש על עזרא 8:35

5) Similarly, R. Yossi said (Ezra 8:35): "Those who came out of the captivity, the children of the exile, offered burnt-offerings to the G d of Israel: twelve bullocks for all Israel, ninety-six rams, seventy-seven sheep, twelve he-goats for a sin-offering, all as burnt-offerings to the L–rd." How can a sin-offering be a burnt-offering! But (the intent is): Just as a burnt-offering is not eaten, so the sin-offering was not eaten. R. Yehudah says: They were brought for (unwitting) idolatry.