The present invention provides a hemostatic porous composite sponge comprising i) a matrix of a biomaterial and ii) one hydrophilic polymeric component comprising reactive groups wherein i) and ii) are associated with each other so that the reactivity of the polymeric component is retained, wherein associated means that - said polymeric component is coated onto a surface of said matrix of a biomaterial, or - said matrix is impregnated with said polymeric material, or - both.