Migrants upset they had been moved from hotels to a detention center north of Athens set fires there in protest during a riot against the move.

The Oinofyta facility had closed last year but reopened to accommodate migrants who are being moved out of hotels, a temporary solution for some who are being moved from islands, where they are some 15,000, to the mainland, where another nearly 50,000 are being kept in camps and centers.

Around 1,500 migrants who had been moved to Attica hotels temporarily are now being transferred to state facilities, officials said and some moved from the islands have been put up in rented homes subsidized by the United Nations refugee agency.

Refugees and migrants are packed in detention centers and camps where even volunteers and NGO’s trying to help can’t cope and as human rights groups complain the facilities are overcrowded and unfit for humans in some instances.

Greek authorities blamed Turkey as tensions between the countries have arched up with near-confrontations in the Aegean and the detention of two Greek soldiers who accidentally strayed across the border during a storm while on patrol in an area of northern Greece which refugees and migrants also use.

One Greek official whose name was not given told Kathimerini that Turkey, which has taken back only a relative handful of those not deemed eligible for asylum, is playing games with the swap deal and continuing to send refugees and migrants in smaller dispatches.

“But they always make sure not to overdo it so they can claim they are honoring the joint EU-Turkey agreement,” the official said, referring to a deal signed between Brussels and Ankara in March 2016 to curb human smuggling.