  Deep Very Large Array radio observations confirm the presence of halo and
relic sources in six clusters of galaxies (A115, A520, A773, A1664, A2254,
A2744) where a wide diffuse emission was previously found in the NRAO VLA Sky
Survey. New images at 1.4 GHz of these six clusters of galaxies are presented
and X-ray data obtained from the ROSAT archive are analyzed. The properties of
clusters hosting radio halos and relics are analyzed and discussed. A
correlation between the halo radio power and the cluster gravitational mass is
presented.
