More than 100 people have been injured after a suspected toxic gas attack on Aleppo.
The Syrian regime and rebels have blamed each other for the attack, which left many suffering from breathing problems, eye inflammation and fainting.
Footage showed medical staff carrying patients on stretchers and helping them with oxygen masks.
Syrian state TV said militants fired shells containing gases that caused choking in three districts of the city.
Rebel officials denied using chemical weapons and accused the Syrian regime of trying to frame them.
Russia, an ally of the regime, claimed it was a chlorine gas attack which poisoned 46 people, including eight children.
Zahal Batal, head of the Aleppo Doctors Syndicate, was less certain.
He said: “We can not know the kinds of gases but we suspected chlorine and treated patients on this basis because of the symptoms.”
A monitoring group said dozens of people suffered breathing problems in Aleppo after the attack, while government shelling killed nine people in a village in Idlib, 41 miles (66km) to the south.
“The explosive (shells) contain toxic gases that led to choking among civilians,” Aleppo police chief Issam al-Shilli told state media.
Abdel-Salam Abdel-Razak, an official from the Nour el-Din al-Zinki insurgent faction, said rebels did not own chemical weapons or have the capacity to produce them.
“The criminal regime, under Russian instructions, is trying to accuse the rebels of using toxic substances in Aleppo. This is purely a lie,” he wrote on Twitter.
Aleppo, for many years a centre of the opposition to Bashar al Assad’s regime, has been back under the control of his forces for nearly two years.