The number of migrants and refugees crammed into overcrowded camps on five Greek islands reached 20,050 on Wednesday, surpassing the 20,000 mark for the first time, according to the latest official data.
The Aegean islands of Lesvos and Samos are particularly affected by the migrant crisis.
Lesvos is currently hosting 10,943 people, with 8,789 living at its Moria reception center, which is designed to hold 3,100.
Conditions are no better on Samos, where a reception center with a capacity of 648 is serving as accommodation for 3,939 people.
A total of 41 people were arrested on Tuesday at airports on the islands of Samos, Mykonos, Santorini, Rhodes and Kos as they tried to leave Greece with fake documents.
