Air strikes that hit a school in Syria’s rebel-held Idlib province killed 22 children and six teachers, the UN children’s agency UNICEF said Wednesday.

“This is a tragedy. It is an outrage. And if deliberate, it is a war crime,” said UNICEF Director Anthony Lake. “Children lost forever to their families … teachers lost forever to their students … one more scar on Syria’s future.”

UNICEF said the airstrikes in the village of Hass in the rebel stronghold of Idlib killed 22 children and six teachers. The Syrian Observatory for Human Rights said the death toll was higher — 35 people — but included fewer children, at 11.

Activist Marwan Hamid, who lives near the scene of the attack, told NPR’s Alison Meuse that “four teachers lost their lives; so did the school custodian. First-responders and neighboring residents were killed in successive strikes. But most of the victims were children.”

A photograph circulated on social media showed a child’s arm, seared off above the elbow, still clutching the strap of a dusty black rucksack.

“When will the world’s revulsion at such barbarity be matched by insistence that this must stop?” added the UNICEF director.

Asked about the attack, Russian Ambassador Vitaly Churkin responded: “It’s horrible, horrible.  I hope we were not involved.”

“It’s easy for me to say ‘no’ but I’m a responsible person. I need to see what our minister of defense is going to say,” he told reporters.

Five schools attacked in Syria since October 11: UNICEF

Five Syrian schools have been attacked since October 11, the UN’s children agency said Friday, October 28.
“Yesterday, when a school compound in Syria was repeatedly attacked, killing dozens of children and teachers, we thought we had seen the depths of depravity,” UNICEF said in a statement.