  A new model of relativistic massive particle with arbitrary spin
(($m,s$)-particle) is suggested. Configuration space of the model is a product
of Minkowski space and two-dimensional sphere, ${\cal M}^6 = {\Bbb R}^{3,1}
\times S^2$. The system describes Zitterbewegung at the classical level.
Together with explicitly realized Poincar\'e symmetry, the action functional
turns out to be invariant under two types of gauge transformations having their
origin in the presence of two Abelian first-class constraints in the Hamilton
formalism. These constraints correspond to strong conservation for the
phase-space counterparts of the Casimir operators of the Poincar\'e group.
Canonical quantization of the model leads to equations on the wave functions
which prove to be equivalent to the relativistic wave equations for the massive
spin-$s$ field.
