Analyticity properties of Graham Witten anomalies

Analytic properties of Graham Witten anomalies are considered. Weyl anomalies according to their analytic properties are of type A (coming from δ-singularities in correlators of several energy momentum tensors) or of type B (originating in counterterms which depend logarithmically on a mass scale). It is argued that all Graham Witten anomalies can be divided into two groups, internal and external, and that all external anomalies are of type B, whereas among internal anomalies there is one term of type A and all the rest are of type B. This argument is checked explicitly for the case of a free scalar field in a six-dimensional space with a two-dimensional submanifold.