SYRIAN war planes attacked rebel-held positions today in response to an apparent poison gas attack on Aleppo.

Air strikes and shelling of encampments south and west of Aleppo were condemned by Free Syrian Army (FSA) spokesman Musafa Seraji as undermining a ceasefire brokered by Russia, which supports the Syrian government, and Turkey, which has provided assistance to jihadist rebels.

The FSA in question is not the group founded by army defectors early in the Syrian war but a Turkish puppet organisation of the same name founded last year to co-ordinate attacks on Kurdish fighters. It stands accused of war crimes after one of its units, the Sultan Murad division, posted videos of Kurdish people’s protection unit (YPG) fighters being tortured.

Rebels have, however, already breached the ceasefire with repeated bombardment of Aleppo. More than 100 people were admitted to hospital on Saturday with symptoms of chlorine gas poisoning following rebel shelling of three neighbourhoods. No deaths were reported and doctors said patients were being treated for breathing problems and blurred vision and two who had been in critical condition had improved.

Russian Defence Ministry spokesman Major General Igor Konashenkov said: “According to preliminary data, the shells that bombarded residential areas were filled with chlorine gas.”

Jihadists also shelled the Christian village of Mahradeh, though residents were able to take shelter in time and no-one was killed. Insurgents occupying the town of Jarjanaz said government strikes had killed eight people, including six children.

Syria’s government has repeatedly accused rebels of using chemical weapons, including in a 2013 assault on Khan al-Assal that killed 25, and Turkish MP Eren Erdem revealed in 2015 that Turkey had shipped sarin gas to rebel groups. His announcement has resulted in his being charged with treason by President Recep Tayyip Erdogan’s government. Rebels have also accused the government of chemical weapons use, claims taken up by the US and Britain to justify bombing Syrian troops.