Adam Clarke on 2 Kings 17:25

The Lord sent lions among them - The land being deprived of its inhabitants, wild beasts would necessarily increase, even without any supernatural intervention; and this the superstitious new comers supposed to be a plague sent upon them, because they did not know how to worship him who was the God of the land; for they thought, like other heathens that every district had its own tutelary deity. Yet it is likely that God did send lions as a scourge on this bad people.