Relief agencies have set up a tent city at Greece's border with Macedonia to cope with the growing number of migrants trying to reach central Europe ahead of winter — with some resorting to extreme measures to complete the journey.

The facilities that have been set up over the past week have a capacity of 1,000 to serve one of the busiest bottlenecks in the country, near the Greek border town of Idomeni.

Syrian English literature student Hussam Jaban, 21, told The Associated Press he swam to a Greek island from the Turkish coast to avoid paying smugglers and keep enough money for the mainland journey through Europe.

"There were 13 of us and we all made it," Jaban said, moments before crossing into Macedonia on foot. "We had a small inflatable boat for a three-year-old child and we pushed it along."

Jaban said it took him four hours to swim from the small Turkish resort of Kas to the eastern Greek island of Castellorizo.

The numbers of migrants arriving to Greece's islands exploded over the summer months, with more than 5,000 people per day making the Aegean Sea journey so far in September, according to the United Nations Refugee Agency, UNHCR.

About 70 percent of the arrivals are from Syria and most continue their journey through Macedonia, Serbia, Croatia and Hungary toward more prosperous northern European nations.

In the past 24 hours, some 4,500 people arrived at the Idomeni crossing, most of them by bus from Athens, Greek police said.

Many often arrive at the same time, overwhelming border control officials who can't process all in one day and are often forced to leave some waiting at the border overnight.

Saleh Labod, 31 from Syria, said he worked as builder in Greece for five years before returning to his village near the war-ravaged city of Aleppo.

He then paid 2,000 euros ($2,250) to a smuggler to travel back to Europe by boat from Bodrum, Turkey to the nearby Greek island of Kos.

"The outboard motor broke when we were 2 kilometers (1.2 miles) away from the shore," he said.

"The smugglers don't care about us at all ... they'll load up a boat with children regardless of the danger. We had to use our hands as oars. We made it: Luckily the weather is still good."

___

Follow Kantouris at http://twitter.com/CostasKantouris

___

Online: UNHCR data on Greece http://goo.gl/e59WO0