1 Samuel 27:9-11

9And David smote the land, and left neither man nor woman alive, and took away the sheep, and the oxen, and the donkeys, and the camels, and the apparel, and returned, and came to Achish.

10And Achish said, Whither have ye made a road to day? And David said, Against the south of Judah, and against the south of the Jerahmeelites, and against the south of the Kenites.1

11And David saved neither man nor woman alive, to bring tidings to Gath, saying, Lest they should tell on us, saying, So did David, and so will be his manner all the while he dwelleth in the country of the Philistines.