I've never seen them eat anything non-vegetarian, but most information online about them mentions eggs, etc. This is the most complete list I found:
"Eastern Chipmunks eat a wide variety of foods, especially acorns and nuts. Other foods they eat include: seeds, some plants, fruits, berries, slugs, snails, insects, baby birds, bird eggs, salamanders, small snakes, young mice, mushrooms, and carrion."
No mention of frogs, but it wouldn't be a stretch.
BB
