The small island of Kos is just one of the places where an unprecedented wave of migrants, many fleeing war, have landed after making a perilous journey across the Mediterranean.
Medical charity Doctors Without Borders raised the alarm Tuesday after disturbing scenes broke out in the Kos stadium as riot police, struggling to contain the crowds, started using fire extinguishers and sonic explosions to disperse them.
Perhaps stung by international outrage over the situation, Greek ministers are meeting Thursday in Athens with the EU commissioner for refugees to try to address the growing crisis.
Altogether, some 124,000 refugees and migrants had arrived in Greece by sea this year as of the end of July, according to the UNHCR -- a "staggering" 750% increase over the same period in 2014.
Migrants faint, fall ill
As about 1,200 migrants lined up in the stadium to be registered Tuesday, some fainted in the blazing heat, Doctors Without Borders said.
They had been ordered to go to the stadium by police who carried out a sweep of parks and public squares where they'd congregated -- for want of any proper facilities to house them -- with only three officers deployed to register them, the charity said. With no shade, toilets or water provided, the situation deteriorated.
Afraid for its staff's safety, Doctors Without Borders pulled its team out of the stadium late Tuesday, but staff members have returned since.
Spokeswoman Julia Kourafa told CNN on Thursday that the police were better organized now, providing water and sandwiches to the migrants. But she said the stadium has only six toilets and a couple of water taps and shouldn't be used in this way.
Doctors Without Borders treated 62 people at the stadium Wednesday, with four being sent to the hospital. Three people were treated as a result of police violence and seven for severe trauma after crowds crushed them, she said. Another 33 were treated for heat exhaustion and loss of consciousness, with children, pregnant women and the elderly the most vulnerable.
"We've been calling for months now to provide the proper reception system that will give humane and decent conditions," Kourafa said.
"Putting people in a stadium or having them live outside is not a solution to the problem. These people are refugees and need to be treated as humans."
Greek police: Migrants leaving island for Athens
A Greek police spokeswoman told CNN that the situation Thursday was calm, with about 1,500 migrants having been taken the day before to the main port in Athens.
Police at the stadium worked into the night Wednesday to process almost 2,500 people claiming to be Syrian refugees and issue documents allowing them to leave the island, the spokeswoman said.
Registration efforts are continuing for another 2,500 people, she said. There were about 5,000 people in the stadium, all thought to be Syrian, she said, but she was unable to confirm exactly how many have left.
Police are also registering migrants from elsewhere in the main police station on Kos, the spokeswoman said.
The number arriving in Kos in July was double that in June, Doctors Without Borders said, "turning a dire situation from bad to worse." The great majority are refugees fleeing war in Syria and Afghanistan, the charity said.
Kos Mayor Yiorgos Kiritsis called Thursday for the European Union to provide emergency financial aid to Greece to help it handle the influx of migrants, saying, "Emergency situations require emergency decisions and measures."
In an earlier statement this week, Kiritsis appealed to the Greek government for help before there was bloodshed and said the idea that all those arriving could be immediately identified was a myth.
"There are 7,000 illegal immigrants in Kos, and 600 to 800 are arriving on a daily basis, so that makes identification impossible," he said.
"In a bid to deal with the problem, the municipality of Kos tried to move the identification process to the stadium; it tried to substitute the State, which is absent from addressing the problem. It has been demonstrated, however, that the problem is no longer manageable."
Greek government sends ship to Kos
Alekos Flambouraris, Greek minister for the coordination of government work, said Thursday that a ship with capacity to house 2,000 to 2,500 people would immediately be sent to Kos to act as a temporary processing center.
"The ship will cover basic accommodation needs; identification will take place (on board), and the difficult situation on the island will be to a large extent alleviated," he said.
"We believe that the EU will assume its responsibilities and will help in the fight against the continuously growing humanitarian crisis."
He said the government was trying to resolve the issue in accordance with international law. Authorities are also working to help migrants camping out in Athens, he said.
Dimitris Avramopoulos, EU commissioner for migration, home affairs and citizenship, is holding an extraordinary meeting Thursday in Athens with Greece's ministers for the interior, migration, public order, maritime affairs and health.
He was also due to speak Thursday with Kiritsis, the Kos mayor.
Avramopoulos is expected to give a televised statement Friday in Brussels, Belgium.
Last week, the EU approved 2.4 billion euros in funding for the migration crisis. Greece will receive 473 million euros as part of this funding, according to the UNHCR.