(REUTERS) – Tensions were high on the Greek island of Chios on Friday after unknown individuals hurled rocks and petrol bombs at a makeshift camp for refugees and migrants, setting facilities on fire, police sources and aid organisations said.

Video footage showed people struggling to put out the flames with blankets. Women and children were evacuated and camped outside a tavern in an incident which erupted overnight Thursday.

It was the second night running of incidents at the facility, a makeshift camp run by the local municipality of the Aegean island. There were incidents on Wednesday when individuals let off fireworks from the camp and outsiders threw stones into the camp.

“Both incidents together have destroyed the places to sleep for some 100 men women and children. Today there was a third incident where …. stones were thrown and one Syrian man was seriously injured to his head and had to be hospitalised,” said Roland Schoenbauer, spokesman for UNHCR Greece.

According to police, there are more than 1,000 refugees and migrants in the Souda Camp on Chios.

Under a European Union deal with Turkey, migrants and refugees arriving after March 20 are to be held in centres set up on five Aegean islands, including Chios, and sent back if their asylum applications are not accepted.

Tensions have boiled over at overcrowded camps on Greece’s islands as the slow processing of asylum requests adds to frustration over living conditions.

“Tensions are not completely new, but the situation is seriously concerning us, because it has deteriorated seriously. The tensions are linked to the overcrowding of the sites,” Schoenbauer said, saying the perpetrators of the incidents should be found and brought to justice.

More than 3,000 migrants and refugees are currently in Chios. The state facilities have a capacity for 1,100 people.

The situation could be eased if authorities improved security around the camp and stepped up efforts to find refugee and migrants alternative accommodation, Schoenbauer told Reuters.

In September, thousands of people fled a migrant camp on the Greek island of Lesbos after fire swept through tents and cabins during violence among residents.

(Reporting by Lefteris Papadimas and Michele Kambas, writing by Renee Maltezou Editing by Jeremy Gaunt)