ATHENS, Greece—At least 16 people died when their boat overturned off the Greek island of Paros in the central Aegean Sea on Friday, in the third maritime disaster involving illegal immigrants this week, the country’s coastguard said. Authorities scrambled a search and rescue operation overnight northwest of Paros. Air and sea assets were deployed to the area, the coastguard said. Greece is one of the main routes into the European Union for migrants from Africa, the Middle East, and beyond, though the flow has tapered off since 2015–2016, when more than a million people traversed the country to other EU states. The country’s semi-official Athens News Agency said the bodies of 12 men, three women, and an infant were recovered from the area. Eighty people were believed to have been on the vessel, which according to the coastguard was believed to have been headed for Italy from Turkey. The circumstances …