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Dissociative double photoionisation processes in H,O are investigated for photon energies in the 34-50eV range. Two fragmentation channels for formation of H++OH+ and a dissociation into three fragments ( O + + H + + H ) are observed. The total kinetic energy released in each of these processes is measured by using the photoion-photoion coincidence (PIPICO) method. The appearance energies of the first two processes measured at 34.4 and 37.1 eV are well below the lowest vertical energy for formation of H20Z+ calculated at 39.2 eV. At least the process at 34.4 eV is considered to be most probably due to two-step double ionisation.