SAMOS – By day, this lush island set in the Aegean Sea offers a sanctuary to tourists seeking clear blue seas and immaculate beaches. After nightfall, a grimmer reality takes hold. Bodies sometimes wash ashore at daybreak. Human traffickers ply the waters off the coast. Patrol boats set off in pursuit of dinghies crammed with desperate migrants. Greece’s islands welcome millions of visitors each year but they are also increasingly playing host to newcomers of a more unwelcome variety: undocumented laborers from Africa, Asia and the Middle East. In fact, Greece’s waters and mountains have become Europe’s primary gateway for illegal immigration: Nearly half of the European Union’s illegal immigrants were detected at the nation’s land or sea borders. Greece says it detained more than 146,000 illegal immigrants in 2008, a 30 percent increase over the previous year and a 54 percent jump from 2006. Greece now has the highest number of illegal entries in the EU, followed by Italy and Spain, EU authorities say. On Samos alone, immigrants arrive at an average rate of 25 a day – a six-fold increase over the past two years – crossing by dinghy, jet-ski or even swimming against fast sea currents. «This very serious problem has gotten worse… We fear that the numbers of illegal crossings will go up even more,» Samos Police Chief Panayiotis Kordonouris said. «We don’t have time to deal with any other police activities.» A detention center built two years ago is already working at double capacity, now housing 500 people, Kordonouris said. Elsewhere, the problem is even more acute. The United Nations Refugee Agency complained to the government last week about conditions on the island of Lesvos, where it said 850 people, including 200 unaccompanied children, were being detained in «cramped and unsanitary conditions.» Shortly afterward, more than 300 people – about a third of them children – were released from detention there and arrived at a port near Athens Wednesday, forcing charities to scramble for temporary accommodation. On top of the sheer volume of migrants seeking a foothold in Europe through Greek waters, authorities are contending with increasingly ruthless, and sometimes ingenious, tactics by the smugglers who bring them in. Coast guard officials say human traffickers tell migrants to tear up their identity documents so they can pose as asylum seekers from war-zones: Most of the foreigners who turn up in Samos say they are from Afghanistan, Somalia or the Palestinian territories. The main sea route is from Turkey to the EU shores of Greek islands as close as 1 mile (about 2 kilometers) away. Under pursuit, Turkish people-smugglers will occasionally throw immigrants overboard, said Samos coast guard chief Stylianos Partsafas. Most of the migrants can’t swim – and sometimes end up floating dead in the sea. «The worst part is the dead bodies we find in the sea,» said Partsafas. «During 2007, we found 34 bodies just in the Samos area.» The immigrants themselves often scuttle their own dinghies, knowing that if they are rescued, they face just a few weeks or months of detention – and then can try to blend into society after being released. If caught on a boat, they’ll just be directed to turn back. «We are people; they are people – and we try to save them,» said Partsafas. «It’s difficult work.» He said Turkish smugglers typically charge each immigrant 1,000 euros ($1,400) for the boat ride to Greece. They work with «facilitators» living in Greece, who try to keep the immigrants hidden from police and buy them batches of ferry tickets to the mainland, Partsafas said. The crisis has prompted the EU to send urgent help to overwhelmed local authorities – one of the biggest projects of Frontex, the bloc’s new border agency based in Warsaw, Poland. Members of the multinational team sent by Frontex describe the unusual challenges of fighting increasingly sophisticated smuggling operations. «The traffickers are getting smarter,» said a Dutch officer who spoke on condition of anonymity because he is not authorized to speak to the media. «We know that they tell the (immigrants) they can apply for asylum in the EU if you come from a war-zone. So we see if they respond to the language of the country they say they come from,» said the officer, who is an expert in document fraud. «Then you might ask them obvious questions – What currency do you use? What is the capital city?» Asylum applications are overwhelmingly rejected, raising concerns from human rights groups and the United Nations refugee agency that legitimate claims are being ignored. Visiting officers from Frontex have arrest powers and can even carry guns. Twenty EU countries are currently helping Greece with personnel and equipment, Frontex spokeswoman Izabella Cooper said. They include translators and officers trained in recognizing the facial features of different ethnic groups. Greek coast guard patrols use radar, satellite navigation and sophisticated night-vision equipment, helped by army observation posts on Samos’s mountains, in their efforts to stop the clandestine boats. Immigrants are typically held for several months and then released with a formal order to leave the country in three weeks. But many end up staying. Often, they end up living in crowded apartments in Athens and other cities, often in squalid conditions, generating fears of a social crisis with unemployment rising and Greece on the brink of recession. This summer, the conservative government announced plans to build a network of mainland detention centers. Police are clearing squats in central Athens, and razed a makeshift camp in the western port of Patras where hundreds of mostly Afghan migrants lived, hoping to travel onto Italy. The action followed an increase in support for an ultranationalist political party as well as a spate violent attacks against immigrants by hate groups.