The blast occurred as thousands of ethnic Armenians fled the breakaway enclave after their fighters were defeated by Azerbaijan in a lightning military operation.

The authorities have not given any explanation of the cause of the blast.

Earlier, several media outlets cited the Armenian health minister as saying the death toll from Monday’s incident had risen to 125.

Some outlets later edited their posts, saying that was the number of people killed in Karabakh during last week’s Azerbaijani military operation and then transported to Armenia.

The office of Karabakh’s ombudsman, Gegham Stepanyan, gave its toll and the number of missing later on Tuesday.

It said on social media the number of injured had reached 290, 168 of whom were taken to medical institutions in Armenia on Tuesday: 96 by helicopters from Armenia and belonging to Russian peacekeepers, and 72 patients by ambulances accompanied by the International Committee of the Red Cross.

The number of victims rose sharply from an earlier announcement by Karabakh authorities reporting 20 dead on Tuesday morning.

As of 16:00 GMT on Tuesday, at least 28,120 of the 120,000 ethnic Armenians who call Nagorno-Karabakh home had already crossed into Armenia, the Armenian government said.

(Writing by Maxim Rodionov; Editing by Gareth Jones, Emelia Sithole-Matarise, Ron Popeski and Alison Williams.)