Let A be a unital C * -algebra with the canonical (H) C * -bundle A over the maximal ideal space of the centre of A, and let E (A) be the set of all elementary operators on A. We consider derivations on A which lie in the completely bounded norm closure of E (A), and show that such derivations are necessarily inner in the case when each fibre of A is a prime C * -algebra. We also consider separable C * -algebras A for which A is an (F) bundle. For these C * -algebras we show that the following conditions are equivalent: E (A) is closed in the operator norm; A as a Banach module over its centre is topologically finitely generated; fibres of A have uniformly finite dimensions, and each restriction bundle of A over a set where its fibres are of constant dimension is of finite type as a vector bundle.