The fire destroyed Greece’s largest migrant camp, the overcrowded Moria facility on the island of Lesbos.
Some 25 firefighters with 10 engines battled the flames as the migrants were evacuated. Some have been injured by exposure to smoke.
Reports say that migrants protesting the coronavirus rules may have started the fire, although this is unconfirmed.
The police blocked the migrants heading to the port city of Mytilene, leaving them stranded on the road.
Moria is home to nearly 13,000 people, more than four times the number it can officially house. According to immigration, about 70% of the people in the camp are from Afghanistan, but immigrants from more than 70 different countries live there.
The deputy governor of Lesbos, Aris Hatzikomninos, reportedly told local radio that the camp was “completely destroyed”. Greek Prime Minister Kyriakos Mitsotakis called an emergency fire meeting on Wednesday morning.
The EU has agreed to finance the transfer of 400 unaccompanied adolescents and children to the continent and their accommodation, according to Ylva Johansson, European Commissioner for Home Affairs.
“The safety and shelter of all people in Moria is a priority,” he tweeted.
A local resident told the BBC that almost the entire camp had caught fire.
“Now with first light, I can see that there are some tents that do it, they are fine, but the rest of the field, as I can see from this distance, is burned,” Thanasis Voulgarakis said.