  They should make it clear, being in Greece illegally is a crime that carries a jail sentence or we, the cash strapped, Judaised-Communised Greek government, will transport you back to your country and then send your country's government the bill for doing so.  If the country of the invaders refuses to pay the bill or take the bums back, Greeks should assist them by catapulting them over the wall of their embassy. They'd soon get the message and word would reach home soon enough that Greece is off limits to uninvited immigrants.