What happened before the last five strong earthquakes in Greece: Facts and open questions

During the period October 2005 - January 2006, five strong earthquakes occurred in Greece as follows: three magnitude 6.0 consecutive earthquakes with almost the same epicenter in the Aegean Sea close to the western coast of Turkey, one magnitude 6.1 in western Greece and one magnitude 6.9 in southern Greece. In March 2005 and September 2005, intense anomalous geoelectric changes were observed at two different stations respectively: one in the Aegean Sea and the other in western Greece. These changes were immediately reported to international journals well in advance of earthquake occurrences. Natural time analysis of seismicity subsequent to the September changes around the epicenter of the last 6.9 earthquake is made. The results indicate that the occurrence time of the 6.9 earthquake can be specified with a narrow range around two days.