  Photon-number correlation measurements are performed on bright squeezed
vacuum states using a standard Bell-test setup, and quantum correlations are
observed for conjugate polarization-frequency modes. We further test the
entanglement witnesses for these states and demonstrate the violation of the
separability criteria, which infers that all the macroscopic Bell states,
containing typically $10^6$ photons per pulse, are polarization entangled. The
study also reveals the symmetry of macroscopic Bell states with respect to
local polarization transformations.
