Reports of gas attack emerge as Syrian government forces continue offensive against rebel-held Damascus suburb.
Health officials in the rebel-held enclave of Eastern Ghouta are accusing Syrian government forces of using poisonous gas in their aerial bombardment campaign in the Damascus suburb.
Syria's Civil Defense, also known as the White Helmets, said on Sunday that women and children in the town of Al-Shifoniyah were experiencing difficulty breathing.
At least one child died as a result of suffocation, they said on their official Twitter account.
Chlorine gas symptoms reported in eastern Ghouta, Syria
The reports of the gas attack come as PresidentBashar al-Assad's forces fight against opposition groups from multiple fronts, in an attempt to penetrate into the besieged enclave.
At least 27 people have been killed on Sunday as a result of shelling by Russian-backed Syrian warplanes, which have been targeting various "districts and towns" across the Damascus suburb, according to Al Jazeera's Mohammed Al Jazaeri, reporting from Eastern Ghouta.
The attacks come after the UN Security Council voted unanimously in favour of a resolution on Sunday, calling for a 30-day ceasefire in Syria.
Last week, deadly air strikes and artillery fire launched by Russian-backed Syrian forces exacerbated a dire humanitarian crisis in the besieged enclave, home to some 400,000 people.
According to the Syrian Observatory for Human Rights (SOHR), more than 500 civilians lost their lives as a result of the aerial bombardment campaign that began on February 18.
Earlier this week, the UN and other international bodies expressed outrage at the number of civilian casualties.
Hundreds of thousands of people have died in fighting during Syria's seven-year civil war, and millions have been forced to flee the country.
