Some women fainted while children cried and men scuffled, as chaos erupted among migrants on the Greek island of Kos.

Overwhelmed Greek authorities are struggling to cope with the arrival of thousands of migrants and refugees landing on the country's shores everyday.

There was commotion outside Kos stadium as hundreds of people queuing to get registered jostled.

As the crowd surged forward towards the door, one woman passed out in the heat while another man appeared to collapse.

Many said the authorities had been unable to provide them with water, shelter, food or sanitation.

The United Nations refugee agency has said about 124,000 migrants have arrived on the shores of Greece this year.

Greek Prime Minister Alexis Tsipras said last week his country's infrastructure simply cannot handle the thousands of migrants.