  We revisit the motion of massless particles with anyonic spin in the horizon
of Kerr--Newman geometry. As recently shown, such particles can move within the
horizon of the black hole due to the coupling of charges associated with a
2-parametric central extension of the 2-dimensional Carroll group to the
magnetic field generated by the black hole -- the so called "anyonic spin-Hall
effect". We show that the previously computed magnetic field is not invariant
under Carroll diffeomorphisms and find another result which respects these
symmetries of the horizon. We also consider a more astrophysically relevant
case of a (weakly charged) rotating back hole placed in a uniform magnetic
field, which could, for instance, be induced by the surrounding plasma. We show
that a qualitatively similar magnetic field assisted anyonic spin-Hall effect
takes place, even in the absence of black hole rotation. The theoretical
possibility of a motion induced by a magnetic monopole is also studied.
