THESSALONIKI – Clashes broke out late on Sunday in a reception centre for refugees and migrants in Lagadiki, outside Thessaloniki. According to the police, six people were injured during the episodes, who were transferred to the Papageorgiou hospital.

The police proceeded to make four arrests.

Police said Monday the three-hour fight in the Lagadikia camp involved about 250 people and apparently broke out after a group of Syrians said a group of Algerians had harassed Syrian women. The fight quickly spread through the camp, with those involved using knives and planks of wood.

Angry at being penned up in detention centers for up to two years, refugees and migrants in Greece are stepping up protests, with some 200 blocking a highway on Sunday near Thessaloniki.

There are some 64,000 of them in the country, stuck after the European Union closed its borders to them and dumped the problem on Greece during a crushing economic and austerity crisis.

That includes more than 15,000 on islands close to Turkey, which lets human traffickers operate even during a suspended European Union swap deal. Only a relative handful have been returned while the numbers of those coming to Greece are picking up fast in the warmer weather.

Conditions in the vastly overcrowded camps and detention centers have been criticized by human rights groups, activists, volunteers and NGO’s who said the facilities aren’t fit in some cases for humans.

The highway protest ended the night of May 5 when riot police showed up to chase off the demonstrators who had left tents that filled with water during torrential rains which hit the country.

The camp where they live, on the site of a former army barracks, houses refugees and other migrants in sturdy containers but tents had to be added with a new influx from Turkey, now increasing across the land border in northern Greece along the Evros River.

Some 270 more landed on Lesbos on May 6, a couple of days after Prime Minister and Radical Left SYRIZA leader Alexis Tsipras went to the island for a growth conference and had to be protected by 300 riot police after islanders protested the lack of action by his government in helping them deal with some 7,000 refugees and migrants.

Another 80 people, of undetermined nationality, landed on Chios off the Turkish coast, another favorite spot for those who went to Turkey after fleeing war and strife in their homelands and are desperate to get into the EU any way they can.

Since May 1, human smugglers in Turkey have landed another 1200 people on Greek islands, the business newspaper Naftemporiki said.

Six people were injured late May 6 during clashes at the Langadika refugee center outside Thessaloniki, said Kathimerini, with police saying more than 200 people were involved.

(Material from the Associated Press and the Athens Macedonian News Agency was used in this report)