Topological insulators (TI) have generated much interest lately both from the point of realizing interesting new physics as well as the possibility of being used as materials in spintronic applications. In topological insulators (TI), strong spin-orbit coupling results in non-trivial scattering processes whose effects are seen in suppressed back scattering weak anti-localization and the possibility of an exotic Kondo effect that mimics graphene. A key, elusive, step in exploring these and other novel electronic phases is the experimental observation of charge backscattering due to spin-flip processes at the surface of a magnetically-doped TI. In this talk I present scanning tunneling microscopy data on prototypical topological insulators, doped Bi2Te3. I will show that the presence of Fe impurities induces new backscattering q-vectors, which were originally forbidden. By comparing the Fourier transform (FFT) of the conductance maps with angle-resolved photoemission spectroscopy data we identify the momentum space origin of these scattering vectors. We perform a model calculation of the FFT patterns showing that the new scatteringď€ vectors are fully consistent with spin-flip scattering. Our combined data therefore present compelling evidence for the first momentum resolved measurement of enhanced backscattering due to magnetic impurities in a prototypical TI.