Greece has bolstered security at a holiday island struggling to process up to 2,500 Syrian and Afghan refugees following scuffles with police.
Many of the refugees have been locked inside a sports stadium on the island of Kos for 18 to 24 hours. Aid workers said many have little or no access to water or shade, causing various refugees to faint and at least one to suffer an epilectic seizure.
Kos mayor Giorgos Kiritsis warned of "bloodshed" if the situation on the island worsened.
Greek Minister Alekos Flabouraris said a ship with a capacity for at least 2,500 people would be dispatched to the island to be converted into a reception centre to process arrivals.
Two riot police units have been dispatched to Kos from Athens and police reinforcements from nearby islands have also been brought in.
"Two units, or 40 men, have arrived in Kos. Other reinforcements are being sent from other eastern Aegean islands," a police spokesman said.
Earlier, skirmishes erupted at a makeshift reception centre at the sports stadium during which police used fire extinguishing spray to disperse people.
Scuffles broke out outside one of compound's two closed gates between riot police and a small group attempting entry. Police threw a tear gas canister to disperse the group of about 40 people and have also reportedly used sonic blasts to maintain order.
Flabourasis said the Greek government was going to do as much as possible to ease the problems facing Kos due to the refugee crisis.
Cash-starved Greece, mired in its worst economic crisis in decades, has found itself in the spotlight in recent months as Europe grapples with a stream of refugees fleeing war and poverty. Tens of thousands have crossed into Greece from Turkey along its long island coastline.
Dozens of tents lined a beachfront promenade leading from Kos's main port on Wednesday. There have been reports of harassment by private security personnel, medical charity Medicins Sans Frontieres (MSF) said.
"The Kos authorities have clearly stated that they have no intention of improving the situation for these people as they believe that this would constitute a 'pull factor,'" said Brice de le Vingne, MSF head of operations.
"But the truth is that people fleeing war will keep on coming whether or not the authorities are trying to stop them from doing so."
A coastguard spokeswoman said more than 200 migrants had been rescued in the past 24 hours on the island. Most arrivals are undocumented.
- with Agencies
