In this article, we evaluate the effectiveness of a pre-classification scheme for the fast retrieval of faces in a large image database. The studied approach is based on a partitioning of the face space through a clustering of face images. Mainly two issues are discussed. How to perform clustering with a non-trivial probabilistic measure of similarity between faces? How to assign face images to all clusters probabilistically to form a robust characterization vector? It is shown experimentally on the FERET face database that, with this simple approach, the cost of a search can be reduced by a factor 6 or 7 with no significant degradation of the performance.