Five civilians were injured in artillery shelling by Syrian regime forces in the northwestern town of Khan Shaykhoun, according to a pro-opposition civil defense official.
Regime forces pounded the town throughout the night, Mohammed Haj Youssef told Anadolu Agency on Monday.
He said one of the injured civilians was in a serious condition.
Khan Shaykhoun is part of a network of de-escalation zones announced by Turkey, Russia and Iran in which acts of aggression would be expressly forbidden.
At least 100 civilians were killed and hundreds injured in a suspected regime chemical attack in Khan Shaykhoun in April.
Syria has been locked in a vicious civil war since early 2011, when the Bashar al-Assad regime cracked down on pro-democracy protests with unexpected ferocity.
Since then, hundreds of thousands of people have been killed and more than 10 million displaced, according to UN officials. Assad regime officials, however, put the conflict's total death toll much lower.
