By CHRISTINE THEODOROU, ENGIN BAS and IBTISSEM GUENFOUD, ABC News

(ISTANBUL, Turkey) — Massive fires have engulfed the Moria migrant camp on the Greek island of Lesvos, where an estimated 12,000 migrants and refugees live, officials said.

Thousands of migrants fled the camp overnight. No casualties have been reported but the registration center of the camp was “largely destroyed,” according to the UN Refugee Agency (UNHCR).

More than 3,000 tents as well as administration offices and a clinic within the camp have been destroyed, according to local media reports. German Foreign Minister Heiko Maas called the fire at Moria a “humanitarian catastrophe.”

The European Union has promised help, with EU official Ylva Johansson announcing “the immediate transfer and accommodation on the mainland of the remaining 400 unaccompanied children and teenagers” living in the camp.

The situation in the camp illustrates the lack of coordinated migration policy in the EU.

Vice president of the EU Commission, Margaritis Schinas, is heading to Greece and a delegation from the Greek government is traveling to Lesvos’ capital of Mitilini to assess the situation.

The overcrowded camp was already a health hazard, human rights groups have repeatedly warned. Lack of health care and access to adequate water, sanitation and hygiene products showed Greek authorities had “not done enough to address the acute overcrowding,” Human Rights Watch said in April. Asylum seekers from over 70 countries are said to be living in Moria, according to InfoMigrants. On Tuesday, some 35 people in the camp had tested positive for COVID-19.

The Greek fire department and emergency services worked on containing the fire, the cause of which has not yet been determined.

The UNHCR, however, mentioned “reports of tensions between people in neighboring villages and asylum seekers” who were trying to reach Mitilini.

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