  We study the dark matter particle, the dark photon (DP), in the decay of the
Higgs-like boson. The nature of dark matter is maintained through the hidden
sector including the effects of breaking of the scale invariance. The model is
based on the additional $U^{\prime}(1)$ gauge group associated with light DP.
The interaction between DP and quarks is mediated by the derivative of the
scalar - the dilaton. The latter appears in the conformal sector which triggers
the electroweak symmetry breaking. Upper limits are set on the DP mass, the
mixing strength between the standard photon and DP. The model does allow to
estimate the DP mass with the value of 4.5 MeV. The maximal value of the scale
invariance breaking constant is also reported.
