  The decays $\mu \rightarrow e \gamma$, $\mu \rightarrow e \gamma \gamma$, and
$\mu \rightarrow e e \bar e$ are analysed in the framework of the Pati-Salam
type quark-lepton symmetry $SU(4)_V \otimes SU(2)_L \otimes G_R$ where the
effects of mixing in the quark-lepton currents are taken into account. It is
shown that the $\mu \rightarrow e \gamma \gamma$ and $\mu \rightarrow e e \bar
e$ decays via the vector leptoquark have not a GIM--type suppression, while the
$\mu \rightarrow e \gamma$ decay has. So, the specific hierarchy of the decay
probabilities could take place $\Gamma(\mu \rightarrow e e \bar e) \gg
\Gamma(\mu \rightarrow e \gamma \gamma) \gg \Gamma(\mu \rightarrow e \gamma)$.
The existing bounds on the vector leptoquark mass and on the mixing matrix
elements, based on the data for the $\mu e$ conversion in nuclei and for the
ratio of the $K_{e 2}$ and $K_{\mu 2}$ decays allow to set the upper limits on
the branching ratios at a level of $10^{-18}$ for the $\mu \rightarrow e \gamma
\gamma$ decay and at a level of $10^{-15}$ for the $\mu \rightarrow e e \bar e$
decay.
