  We show that in 2+1 dimensional Quantum Electrodynamics an external magnetic
field applied to a finite density of massless fermions is screened, due to a
$2+1$-dimensional realization of the underlying $2$-dimensional axial anomaly
of the space components of the electric current. This is shown to imply
screening of the magnetic field, i.e., the Meissner effect. We discuss the
physical implications of this result.
