Via Defence Greece (h/t Jan Simonsens blogg):
Until now Greece does not seem to have a particular issue of Islamic fundamentalism. Nevertheless, as aptly described in a 2009 U.S. State Department report on terrorism, “Greece is increasingly an E.U. entry point for illegal immigrants coming from the Middle East and South Asia, and there was concern that it could be used as a transit route for terrorists travelling to Europe and the United States. The number of illegal immigrants entering Greece, especially through the Aegean Sea, increased dramatically in 2008 and 2009, with more than 100,000 illegal immigrants, nearly half of whom originated from North Africa, the Middle East and South Asia, arrested each year.”
Presently in Greece, there seems to be activity within radical Islamic elements as well as gradual projection of Islamic political entities through the use of Greek nationals.