  We present a model where neutrino masses are generated by a combination of
spontaneous R-parity violation and Type III seesaw. In addition to the usual
MSSM particle content, our model consists of one extra triplet matter chiral
superfield containing heavy SU(2) triplet fermions and its superpartners.
R-parity is broken spontaneously when the sneutrinos associated with the one
heavy neutrino as well as the three light neutrinos get vacuum expectation
values, giving rise to the mixed $8\times 8$ neutralino-neutrino mass matrix.
We show that our model can comfortably explain all the existing neutrino
oscillation data. Due to the presence of the triplet fermion, we have a pair of
additional heavy charged leptons which mix with the standard model charged
leptons and the charginos. This gives rise to a $6\times 6$ chargino-charged
lepton mass matrix, with 6 massive eigenstates. Finally we discuss about the
different R-parity violating possible decay modes and the distinctive collider
signatures which our model offers.
