The latest developments in Europe's immigration crisis (all times local):

8:55 a.m.

Greece's coast guard says at least 21 people have died in two separate sinkings of boats smuggling migrants off two Greek islands overnight. Dozens have survived, and a search and rescue operation is underway for more potential survivors.

The coast guard says a wooden boat carrying 48 people sank in the early hours of Friday off the small island of Farmakonissi in the eastern Aegean. Forty of the passengers managed to make it to shore, while authorities rescued one girl and recovered seven bodies from the sea.

In a separate incident, a wooden sailboat carrying an undetermined number of people sank off the island of Kalolimnos.

The coast guard rescued 26 people and recovered 14 bodies. Coast guard vessels, a helicopter and private boats are searching for survivors.