The bus set ablaze at Burgas Airport in Bulgaria is thought to have been carrying a large party of young Israelis. Witnesses told Israeli media that the huge blast occurred soon after someone boarded the vehicle.
Israeli Foreign Ministry spokesman Jonathan Rosenzweig said a flight from Tel Aviv had landed at 4:45pm and that the blast took place about 40 minutes later.
"We don't know if it was a terror attack," said Paul Hirschson, another spokesman for the ministry. "We do know it was an explosion."
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