  We discuss an application of dynamical multi-parton interaction model, tuned
to measurements of underlying event topology, for a description of destroying
rapidity gaps in the jet-gap-jet processes at the LHC. We concentrate on the
dynamical origin of the mechanism of destroying the rapidity gap. The cross
section for jet-gap-jet is calculated within LL BFKL approximation. We discuss
the topology of final states without and with the MPI effects. We discuss some
examples of selected kinematical situations (fixed jet rapidities and
transverse momenta) as distributions averaged over the dynamics of the
jet-gap-jet scattering. The color-singlet ladder exchange amplitude for the
partonic subprocess is implemented into the \textsc{Pythia 8} generator, which
is then used for hadronisation and for the simulation of the MPI effects.
Several differential distributions are shown and discussed. We present the
ratio of cross section calculated with and without MPI effects as a function of
rapidity gap in between the jets.
