  Two new expanding X-ray rings were detected by the Swift XRT instrument
during early follow-up observations of GRB 061019 and GRB 070129, increasing to
5 the number of dust scattering X-ray halos observed around GRBs. Although
these two halos were particularly faint, a sensitive analysis can be performed
that optimizes the method originally developed by Tiengo & Mereghetti (2006) to
analyze dust scattering rings observed with XMM-Newton for the Swift satellite.
In the case of GRB 061019, a known giant molecular cloud is identified as the
one responsible for the scattering process, and its distance is accurately
measured (d=940$\pm$40 pc) through the dynamics of the expanding ring. In the
second case, XRT observed both the main peak of the prompt emission of GRB
070129 and the scattering halo, but the small number of detected halo photons
prevents us from distinguish between different dust models.
