Jerboa!
יהוה plagued the Philistines with piles [or hemoridal tumors] and with an infestation of jerboas; as a result of them having captured and carried the Ark of the Covenant into their homeland. (1 Samuel 6:4-5 & 11 & 18) They set it in their temple next to their god Dagon, causing his destruction. (1 Sam 5:1-5) Many people died as a result of the jerboa infestation and from the piles. Some have speculated the jerboas infected the people with bubonic plague [which jerboa's have been associated with in the past] or with some other disease. Maybe the jerboas simply consumed and/or destroyed all the food so the people starved. In any case, the Philistines rightly attributed the plagues upon them with them having the Ark of the Covenant of the true God in their possession. So, they anxiously sought a way to send it back to the Jews. (1 Samuel 4-6)