Syria’s official news agency says foreign-backed militants have used “poisonous” weapons to attack government soldiers in a suburb of the country’s capital.
“Terrorist organizations yesterday attacked a Syrian Army position in Eastern Ghouta, in the Damascus countryside, using poisonous substances,” the Syrian Arab News Agency (SANA) reported.
The materials “had effects on the nervous system which harmed a number of the troops by suffocation and respiratory problems,” it added.
Television footage, meanwhile, showed troops struggling to breathe, with one soldier saying those affected had experienced “a feeling of almost paralysis and an increase in saliva in the mouth.”
Another soldier, interviewed in hospital, said a "smoke bomb" landed and then he started to feel the symptoms.
Damascus surrendered its stockpiles of chemical weapons to a joint mission led by the United Nations and the Organization for the Prohibition of Chemical Weapons (OPCW) following an attack in Ghouta two years ago.
UN investigators established that sarin gas was used in Eastern Ghouta in the 2013 attack which allegedly killed 1,429 people, including at least 426 children.
The chemical attack came amid a red line set by the US to attack the Syrian government if it used chemical weapons in fighting foreign-backed militants.
The US government then came under pressure to mount airstrikes on Syria but Washington reportedly found no hard evidence of a government involvement to make a case for an offensive.
According to reports, the rockets used in the assault were handmade and contained sarin.
Last December, Ahmed al-Gaddafi al-Qahsi, a cousin of former Libyan dictator Muammar Gaddafi, alleged that the chemical weapons used in Ghouta were stolen from Libya and later smuggled into Syria via Turkey.
The United Nations has confirmed that both mustard and chlorine gas have been used possibly by Daesh and other militants in attacks during the war in Syria and Iraq.
'Playing game' with Nusra Front
On Thursday, Russia's foreign minister said he believes the US may hope to use al-Qaeda's branch in Syria to unseat Syrian President Bashar Assad's government.
Sergei Lavrov said in St. Petersburg that the reluctance of US-backed opposition groups to distance themselves from the Nusra Front has been a major reason behind continuing fighting.
The US could be "playing some kind of game here, and they may want to keep al-Nusra in some form and use it to topple the regime," Lavrov said.
Lavrov added that he raised the issue in a recent phone conversation with US Secretary of State John Kerry who denied any such plans.
"But why then the Americans with all their potential can't force the units they have been working with to leave the territories controlled by bandits and terrorists," Lavrov said.
Russia at some point issued an ultimatum for opposition units to leave Nusra-controlled areas or face airstrikes, but later agreed to give more time for them to pull out.
Spared the Russian strikes, Nusra has used the moment to replenish its supplies and receive reinforcements, Lavrov said.
A senior US defense official said Thursday that Russian aircraft conducted a series of airstrikes in Syria against US-backed forces.