Syria's regime dropped chemical weapons from a plane on a district of Aleppo earlier this month, killing two infants and a woman, experts say.
This fresh evidence of poison attacks on civilians pointed to a revenge on Kurdish residents of Sheikh Massoud, in the north of the country's largest city, for their recent defection from the regime to join the rebels.
The disclosure was made yesterday as an Israeli general, Brigadier General Itai Brun, declared that Damascus had regularly used banned materials against rebels.
Niazi Habash, a British-trained doctor who treated the Aleppo victims, said they showed symptoms of exposure to chemicals, including breathing difficulties, foaming at the mouth and pinprick pupils.
Apart from the dead, the attack on April 13 injured at least 15 people.
Witnesses said the victims displayed the symptoms after a regime aircraft dropped containers that exploded and scattered their contents across a wide area of Sheikh Massoud.
Dr Habash administered doses of Atropine, the recognised antidote for chemical weapons, to treat the injured at a clinic north of the city.
Yehia, aged just four months, Abu Bakr Younis (18 months) and Ghadeer Neddaf, an adult, died of respiratory failure.
It is the fourth credible report of chemical weapons being used in a Syrian attack in recent months. After studying a video posted on Dr Habash's Facebook page, experts said the effects appeared similar to those suffered by Syrian villagers in Khan al-Assad, near Aleppo, last month.
Hamish de Bretton-Gordon, a former British army specialist and director of a biological consultancy, said the most likely explanation was the chemical sarin had been used.
"From what we've seen, and the descriptions of containers being dropped from the air, it certainly seems that the regime is using sarin in an unprepared state in these attacks," he said.
A soil sample from Khan al-Assad spirited out of Syria by MI6 tested positive for a chemical agent, a fact confirmed last week by William Hague, Britain's foreign secretary.
John Kerry, the US secretary of state, said Israel's prime minister Benjamin Netanyahu had not been able to confirm to him yesterday that the Syrian regime had used chemical weapons against rebels."I do not know yet what the facts are," he said. (© Daily Telegraph, London)