Five people, including a baby and two children, drowned and one was missing in two separate incidents of migrants trying to reach Greece from nearby Turkey on Sunday, the Greek coastguard said.

The service said a sail boat early on Sunday reported it had recovered the body of a baby and had rescued 11 migrants off the Kastellorizo island. The coast guard, which then rushed to the spot, recovered the corpses of another two women and a boy, while it was looking for a missing man, it said.

Thousands of refugees - mostly fleeing war-torn Syria, Afghanistan and Iraq - attempt daily to cross the Aegean Sea from neighbouring Turkey, a short trip but a perilous one in the inflatable boats the migrants use, often in rough seas.

Almost 400,000 people have arrived in Greece this year, according to the UN refugee agency UNHCR, overwhelming the cash-strapped nation’s capacity.

In a separate incident, a boy, part of a group of about 110 people, drowned when he fell off a boat en route to the island of Farmakonisi. The rest of the people managed to get ashore.

The EU has offered Turkey €3 billion in aid and the prospect of easier travel visas and “re-energised“ talks on joining the bloc if it helps stem the flow across its territory.

Earlier, around 40 buses packed with migrants queued to enter Croatia from Serbia, their passage to western Europe slowed by a new diversion through Slovenia as weather conditions worsen.

Many had spent the night on the buses, wrapped in warm clothes and blankets against the autumn cold. They woke to dense fog.

“This part of the trip has lasted 20 hours, and we’ve been here for almost 12 hours,” said Khair (40) a former sales manager from the Syrian capital, Damascus. “What can we do? We’re here and we have to wait.”

Hungary sealed its southern border with Croatia to migrants at midnight on Friday, forcing them west to fellow EU member Slovenia, a small former Yugoslav republic of two million people that also borders Austria.

Some 3,000 entered Slovenia on Saturday, en route to Austria and Germany, the favoured destination of the vast majority, many of them Syrians fleeing war.

But Slovenian authorities said they planned to limit the influx to around 2,500 per day in line with the country’s capacity to register and accommodate them.

That threatened to create a backlog in Croatia and Serbia which in recent weeks have seen upwards of 5,000 crossing their borders every day.

Aid agencies are concerned about backlogs building in the Balkans, lashed by autumn winds and rain and with winter on its way.

Croatia and Slovenia have both said they will not stop migrants from crossing, providing Austria and Germany also keep their doors open.

Reuters