RobH_en_tn/jer/41/07.md

It came about that

This phrase is used here to mark an important event in the story. If your language has a way for doing this, you could consider using it here.

Ishmael son of Nethaniah slaughtered them and threw them into a pit, he and the men who were with him

It is stated it in Jeremiah 41:8 that Ishmael and his men did not kill all 80 men. You can state here that they killed most of the 80 men. Alternate translation: "Ishmael son of Nethaniah, and the men who were with him, killed most of the 80 men and threw them into a pit"