By Stoyan Nenov
IDOMENI, Greece (Reuters) - Greece on Sunday condemned as "dangerous and deplorable" the use of teargas by the Macedonian police against crowds of migrants gathered on the Greek side of the border at Idomeni, an outpost where thousands are waiting for shuttered borders to reopen.
Earlier attempts by a large group to cross the border fence prompted skirmishes with police, a Macedonian official said. Aid organisations at the camp said some migrants were wounded and police in Skopje said three officers were also hurt.
More than 10,000 migrants and refugees have been stranded at Idomeni since February after a cascade of border shutdowns throughout the Balkans closed off their route to central and western Europe.
Greece said police on the Macedonian side of their joint frontier used teargas, rubber bullets and stun grenades to push back the migrants. Macedonian authorities would only confirm they used teargas.
More than a million people fleeing conflict poured into Europe mainly through Greece in the past year. The European Union is implementing an accord under which all new arrivals to Greece will be sent back to Turkey if they do not meet asylum criteria.
A Macedonian official who asked to remain anonymous said that a large group of migrants left Idomeni camp on Sunday morning and stormed towards the fence.
"They threw rocks at the Macedonian police. The police fired tear gas in response," the official said.
"The migrants were pushing against the fence but standing on the Greek side of the border. The fence is still there, they have not broken through."
Reuters witnesses said a small group of migrants attempted to talk to Macedonian border guards, asking for them to open the border. After given a negative response, they and other migrants started walking towards the fence.
Macedonian police fired teargas, and some migrants hurled back some gas canisters and rocks, they said.
"INDISCRIMINATE FORCE"
In an unusually strong statement, George Kyritsis, a spokesman for migration coordinators in the Greek government, said the use of force was unacceptable.
"The indiscriminate use of chemicals, rubber bullets and stun grenades against vulnerable populations, and particularly without reasons for such force, is a dangerous and deplorable act," Kyritsis said.
More than 50,000 refugees and migrants have been stranded in Greece as a result of the border shutdowns. By Sunday morning, there were more than 11,200 people at Idomeni.
"We urge the authorities of FYROM to comprehend the potential risks the use of violence against refugees and migrants entails," said Kyritsis, referring to the official title of the neighbouring country, Former Yugoslav Republic of Macedonia.
Athens has long refused to accept its neighbour as just 'Macedonia'. Some Greeks fear accepting 'Macedonia' could provide a basis for territorial claims by that country on a northern Greek province of the same name.
In Skopje, a police spokesman said only tear gas was used after migrants stormed towards a border fence on Sunday. Three police officers were wounded.
"We used teargas but I haven't heard anything about rubber bullets," a Macedonian police spokesman said. The situation at the border was under control but still tense, he added.
Aid organisations said they were treating people for tear gas exposure.
"We have injuries and are extremely busy," a senior official for medical charity MSF told Reuters. Another aid organisation also confirmed some migrants were wounded.
Greek authorities have been trying to convince the population to move to reception camps, but migrants have been refusing to move.
(Additional reporting By Renee Maltezou, Kole Casule, Ayat Basma and Sergiy Karazy; Writing by Michele Kambas; Editing by Raissa Kasolowsky)