Fish Baked A La Napolitano

6 white fish fillets
2 tb olive oil
1 onion; chopped
1 15 oz. tomato sauce
2 cloves garlic; chopped
12 olives; pitted and chopped
1 tb capers
1 tb fresh parsley; chopped
2 ribs celery; finely chopped
salt and pepper; to taste

Preheat oven to 375 degrees. Arrange fish in a single layer in an oiled, shallow, covered baking dish. Heat olive oil in a skillet and sauté onion until translucent. Add tomato sauce, garlic, salt and pepper. Cook, stirring occasionally for 5 minutes. Add olives, capers, parsley and celery. Continue cooking 2 minutes longer. Spoon sauce over fillets, cover and bake 25 minutes.