When I was in Italy, the whole Ex-Jugoslavia war happened.
Italy, Greece and surrounding countries where flushed by millions of refugees and a few hundred thousand unwanted criminals.

In Italy we would try to catch them in the water and force them to turn the boat around (it never really worked). At the end we would bring them to shore, bathe them, feed them, put them on a bus and send them back to their country...Also never happened. They ended up finding a plcae to stay or just plain and simple: escaped.

The greeks?
They did it the right way. They welcomed the unwanted with machine guns at the shore. They would usually turn their boat and head for Italy.