Syrian activists have accused government forces of using chemical weapons in attacks Wednesday that killed dozens of people near the capital, Damascus.
The Britain-based Syrian Observatory for Human Rights said the military fired rockets at sites in Eastern Ghouta and Western Ghouta. It cited activists in the area who said "poisonous gasses" were used.
The opposition Local Coordination Committee also said gasses had been used in the assaults Wednesday.
Syria denied the reports.
The violence comes as United Nations chemical weapons inspectors carry out a two-week mission in Syria to investigate earlier incidents in which the Syrian government and rebels accused each other of carrying out chemical attacks.
The inspectors will try to establish only whether chemical weapons - including sarin and other toxic nerve agents - were used, not who used them.
The mission will be limited to investigating the alleged use of chemical weapons in three areas, including a March attack in the Aleppo suburb of Khan al-Assal.