We define a nontrivial homomorphism from the Hecke algebra of type $B$
onto a reduced algebra of the Hecke algebra of type $A$ at roots of
unity. We use this homomorphism to describe semisimple quotients of
the Hecke algebra of type $B$ at roots of unity. Using these quotients
we determine subfactors obtained from the inclusion of Hecke algebra
of type $A$ into Hecke algebras of type $B$. We also study
intermediate subfactors related to the Hecke algebra of type $D$.