Greece's government on Monday said it is preparing a rent-assistance program to help the growing number of migrants in the country who are faced with the oncoming winter and mounting resistance against their arrival elsewhere in Europe.

Olga Gerovasili, a government spokeswoman, said the scheme could cover up to 20,000 migrants and serve as an alternative to a European Union proposal to house them in camps. She said Athens had rejected that proposal Sunday at a meeting of European countries affected by the crisis, insisting that "there will be no concentration camps in our country."

Greece's financial crisis has hammered its once booming real estate market with house prices falling about 40 percent in five years, according to industry estimates, and with a sharp rise in the number of vacant or underused apartments.

Gerovasili indicated the housing program would require financial support from the European Union.

Leftwing Prime Minister Alexis Tsipras has agreed to boost Greece's reception capacity for migrants fleeing conflict and poverty in the Middle East, Asia and Africa to 50,000 by the end of the year from a previous target of 30,000, with the additional 20,000 being absorbed by the new program.

Elected in January, Tsipras' government closed down detention camps for migrants and is promoting voluntary shelter schemes. But those passing through Greece on their way toward more prosperous European countries have shown little interest in using Olympic venues from the 2004 Games in Athens that were reopened this month, fearing they might eventually not be allowed to leave.

"What was asked of us — to place 20,000 in a giant camp — has been rejected. And a discussion was opened into how the real economy can be bolstered and on a more human level, how we can receive refugees," Gerovasili told private Parapolitika radio.

The number of migrants traveling through Greece has risen sharply in recent days, with police reporting that 8,300 people passed the busy Idomeni border crossing between Greece and Macedonia in the 24 hours before Saturday morning — compared to a recent average of some 3,500.

Overnight temperatures in Idomeni reached 3 degrees Celsius (37.4 Fahrenheit) early Monday, and migrants took shelter in tents set up by charities or around campfires outside.

Among them was 35-year-old Ali Nik Bayan, an Iranian who said he spent more than two years in prison for alleged dissident activity.

"When I got out of jail I was approached by the secret service and they demanded I work with them. When I refused, they threatened to arrest my parents and burn my house down," he said. "That's my story: you tell me if I'm a migrant or a refugee."

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