JDG 20:34

34 Then [while the men of Gibeah were running out of the city toward them], the other 10,000 Israelis came out from the places where they had been hiding, west of Gibeah. They were men who had come from all parts of Israel. There was a very big battle. But the men of the tribe of Benjamin did not know that they were about to suffer a disastrous defeat.