Judges 14:19

14:19 The Lord’s spirit empowered him. He went down to Ashkelon and murdered thirty men. He took their clothes and gave them to the men who had solved the riddle. He was furious as he went back home.

Judges 20:31

20:31 The Benjaminites attacked the army, leaving the city unguarded. They began to strike down their enemy just as they had done before. On the main roads (one leads to Bethel, the other to Gibeah) and in the field, they struck down about thirty Israelites.