In the minimal left-right symmetric model which could accommodate the tiny neutrino masses via TeV seesaw mechanism, the neutral scalar from the right-handed symmetry breaking sector could be much lighter than the electroweak scale. We discuss the constraints on this particle from low-energy flavor observables, e.g. meson oscillations and rare decays, and find that such a light particle is necessarily long-lived, and can be searched for at the LHC via displaced signals of a collimated photon jet, if its mass is of order GeV scale. This decay mode provides a new test of TeV scale left-right model.