And the people flew upon the spoil, and took sheep, and oxen, and calves, and slew them on the ground: and the people did eat them with the blood. (1 Samuel 14:32)
It was evening and the people were released from their vows (see v. 24). In their hunger they slew both oxen and calves, and in their haste neglected to dispose of the blood properly (Lev. 17:10-14).