While the fire was brought under control and there were no casualties, thousands of migrants were forced to flee the camp overnight which was largely destroyed.
“Our teams saw the fire spread across Moria and rage all night long," said Marco Sandrone, MSF field coordinator in Lesbos. "The whole place was engulfed in flames. We saw an exodus of people from a burning hell with no direction. Children scared and parents in shock."
Four-hundred unaccompanied minors living at the camp will be brought to the mainland where they will be tested for COVID-19 and quarantined until their results are confirmed, officials said.
Of the 3,500 asylum seekers living at the camp, 1,000 will be housed on a BlueStar Ferry at the port of Mytilini. Two additional Greek naval warships will arrive on Thursday to house the remaining 2,500. Tents will be brought in for the estimated 9,200 migrants to live in unaffected areas around the camp.
The exact circumstances around the fire are still being investigated, but Greek government officials said it was started by camp residents in response to a mandated COVID-19 lockdown after positive cases were identified at the facility last week.
"It is a given that it was started by asylum seekers," Greek Interior Minister Takis Theodorikakos said in Mytilini.
The first COVID-19 case was recorded at the Moria facility on Sept. 2. A total of 2,000 COVID-19 tests have now been carried out at the facility, and 35 positive cases diagnosed.
The fact that this incident occurred days after the first COVID-19 cases were confirmed at the camp comes as no surprise, MSF said in a statement. The organization describes the camp as an "island prison" with increased restrictions.
Asylum seekers from over 70 countries are said to be living in Moria, according to InfoMigrants.
The overcrowded camp was already a health hazard, human rights groups have repeatedly warned. Initially built to accommodate up to 3,000, it has now exceeded that capacity by nearly 10,000, forcing many residents to live outside the camp's walls and without access to electricity, adequate water or sanitation. Human Rights Watch said in April that Greek authorities had "not done enough to address the acute overcrowding."
Greek Minister for Immigration and Asylum Notis Mitarachis said that respect for legal order is a mandatory condition for asylum requests and that delinquent behavior "will not go unpunished."
Rising tensions have also been reported between migrants and locals.
"The whole island is in a state of emergency," Greek Prime Minister Kyriakos Mitsotakis said on Wednesday, adding that all available resources will be deployed to assist.
"Our priority remains the health and safety of all: residents and immigrants," he said.
The European Union has promised to help, but the situation in the camp illustrates the lack of coordinated migration policy in the EU.
European Parliament President David Sassoli said he's been informed that European Commission President Margaritis Schinas will travel to Lesvos on Thursday to assess the situation.
"It's high time for stronger EU solidarity in managing asylum and migration," he said.