An explosion at a fuel depot in Nagorno-Karabakh has killed 20 people and injured hundreds more, local Armenian authorities say.

Nearly 300 people were admitted to hospitals, with dozens of them “still in critical condition”.

It comes as the Armenian government said 13,350 refugees had crossed into the country from the enclave.

The disputed region in Azerbaijan is home to a majority of some 120,000 ethnic Armenians.

Petrol stations were overwhelmed as thousands tried to leave the region, which was already suffering from a fuel shortage following a months-long blockade.

They said doctors were working in “difficult and cramped conditions” to save lives and treat 290 patients with various degrees of burns.

Human Rights Ombudsman Gegham Stepanyan wrote on social media: “The health condition of the majority is severe or extremely severe. The medical capacities of Nagorno-Karabakh are not enough.”

The Armenian health ministry said it was sending helicopters to evacuate patients from the region’s strained hospitals. Azerbaijan also said it had sent medical supplies.

Since Azerbaijan’s seizure of Nagorno-Karabakh last week, thousands of people have left the area after the Armenian government in Yerevan announced plans to move those made homeless by the fighting.

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