An explosion at a weapons depot in Syria has killed at least 67 civilians, toppling a five-story building in the process, an opposition group said. The Syrian Civil Defence – also know as the White Helmets – said a blast in the northern village of Sarmada, located near the border with Turkey, "killed and wounded dozens" on Sunday. Rescue workers used bulldozers to clear the rubble and rescue trapped people. The facade of a building behind the rubble was scorched black from the blast. The Syrian Observatory for Human Rights, a UK-based organisation, placed the death toll at 69, including 17 children. It was unclear if all of the casualties were civilians. "The explosion occurred in a weapons depot in a residential building in Sarmada," Rami Abdel Rahman, the head of the Britain based monitor said. But the cause of the blast was "not yet clear", Mr Abdel Rahman added. The Observatory said an arms depot in the basement of a building run by an arms dealer close to the Al Qaeda-linked Hayat Tahrir Al Sham exploded. It was unclear what caused the blast. Meanwhile, Syrian government forces are fighting rebels in Idlib province. <strong>_______________</strong> <strong>Read more:</strong> <strong><a href="https://www.thenational.ae/world/mena/syrian-anti-air-unit-engage-enemy-target-as-regime-gears-up-for-idlib-push-1.758757">Syrian anti-air unit engage 'enemy target' as regime gears up for Idlib push</a></strong> <strong><a href="https://www.thenational.ae/world/mena/syrian-regime-shells-idlib-ahead-of-assault-1.758543">Syrian regime shells Idlib ahead of </a></strong><strong><a href="https://www.thenational.ae/world/mena/syrian-regime-shells-idlib-ahead-of-assault-1.758543">assault</a></strong>