1 Samuel 14:21-22

Moreover the Hebrews that were with the Philistines before that time, which went up with them into the camp from the country round about, even they also turned to be with the Israelites that were with Saul and Jonathan. Likewise all the men of Israel which had hid themselves in mount Ephraim, when they heard that the Philistines fled, even they also followed hard after them in the battle.