Greece faces an "unprecedented" emergency as migrants fleeing war and poverty arrive on the country's islands in huge numbers, the U.N. refugee agency said Friday. The U.N. High Commissioner for Refugees (UNHCR) said more than 77,000 people have arrived in Greece by sea this year, an average of 1,000 per day, overwhelming local authorities. The country's fragile economic situation is severely straining its ability to address the influx, the agency said. "Greece is part of the European Union, and this is happening in Europe," UNHCR spokesman William Spindler said in Geneva. "We would like the European Union to have a much more active role in responding to the situation in Greece."