We present preliminary results from a novel search for X-ray Line Emitting Objects (XLEOs) in XMM-Newton images. Among the sources found, a high fraction is most likely constituted by extremely absorbed AGN characterized by a column density NH ~ 10^24 cm-2 or more. Their redshift, up to z = 2.0, has been directly determined from the X-ray data, interpreting the detected emission line as a 6.4 keV Fe line. These results demonstrate the success of our search method and imply that a large sample of such objects can be obtained from the public XMM-Newton data archive. If our findings are confirmed by a more extensive analysis and by follow up studies of the newly discovered objects, we may have unlocked the doors to the long sought large sample of highly absorbed, Compton thick AGNs, a key to the Cosmic X-ray Background synthesis models.