Footage has emerged of a grieving father burying his nine-month-old twins after they were killed by a suspected chemical attack in Syria.
Syrian Abdel Hameed al Youssef's children were among at least 72 people believed to have been killed in the attack on the town of Khan Sheikhoun in Idlib on Tuesday.
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Witnesses said victims choked, fainted and foamed at the mouth after the weapons were dropped.
Medical charity Medecins Sans Frontieres said it treated patients with dilated pupils, muscle spasms and involuntary defecation "consistent with exposure to neuro-toxic agents such as Sarin".
Mr al Youssef was supported by two other men as he walked through a cemetery weeping and pointing to the gravestones of family and friends killed in the attack.
The 29-year-old said: "I saw my wife and kids in front of me, martyred. They were twins."
"We buried them. I took Ahmed and Aya and buried them with my brothers. I buried my kids with my own hands. My wife and my brothers."
"My Aya, my Aya (his daughter). Take care of the kids, Dalal (his wife).
"I used to call them (children) blondies.
"I told them I would never ever leave them, my loves, my Aya. They would hold on to me like this and call out to me."
He described the attack as "an airstrike by the criminal air force", saying he had taken his wife and children out of their house but, 10 minutes later, "we could smell it and my children couldn't handle it anymore".
His wife and children and been "martyred" in front of him, he added.
"Every half hour someone comes in and says they found seven more who suffocated here or there.
"The numbers kept rising - 60 people, 70 people, they kept bringing people in, martyred, suffocated."
Earlier, he had urged his cousin to film him as he held the bodies of the twins Aya and Ahmed.
"Say goodbye my loves, say goodbye," he said as he cradled them while sitting in a car.
Mr al Youssef's cousin's wife Aya Fadel pleaded with people outside Syria to do something to help.
"Please don't be silent anymore. Please stop it, please save those scared children. Your silence kills us. Move, change, do anything to save Syrians. Enough is enough," she said.
The airstrikes have been blamed on President Bashar al Assad's military , but the government has denied using chemical weapons.
Russia has said the deaths and injuries were caused when a Syrian airstrike hit a "terrorist warehouse" containing "toxic substances".
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