  This work makes use of the VST observations to select variable sources. We
use also the IR photometry, SED fitting and X-ray information where available
to confirm the nature of the AGN candidates. The IR data, available over the
full survey area, allow to confirm the consistency of the variability selection
with the IR color selection method, while the detection of variability may
prove useful to detect the presence of an AGN in IR selected starburst
galaxies.
