  We have investigated the three vector boson production in electron-electron
collisions in the framework of the left-right symmetric electroweak model. The
process occurs due to lepton number violating interactions mediated by Majorana
neutrinos and triplet Higgs scalars. We find that only the reactions with a
heavy gauge boson pair in the final state, $e^-e^-\to W^{-}_2 W^{-}_2\gamma$
and $e^-e^- \to W^{-}_2 W^{-}_2Z^0_1$, are phenomenologically interesting from
the point of view of the Next Linear Collider. If the mass of $W_2^-$ is 0.5
TeV and the mass of the heavy Majorana neutrino of the order of 1 TeV, the
cross section of both reactions is in the range 1 to 10 fb at $\sqrt{s}= 2$
TeV, depending on the mass of the doubly charged triplet Higgs $\delta^{--}$,
yielding a 1 % background for the pair production of $W_2^-$. At the
$\delta^{--}$ resonance the cross section can be as large as 1 pb.
