Beirut: Three civilians including two children were killed in air strikes on a rebel-held town in northwest Syria today, the fourth full day of a strained truce, a monitor said.
Another 13 civilians were wounded in the strikes on Khan Sheikhun in Idlib province, the Syrian Observatory for Human Rights said.
Observatory head Rami Abdel Rahman said they were the first deaths in air strikes on an area not held by the Islamic State jihadist group since the truce came into force on Monday.
The Britain-based monitoring group could not identify which war planes carried out the raids, although the government and its Russian ally have regularly bombarded Idlib province.
Like almost all of Idlib, Khan Sheikhun is held by an alliance of rebels, hardline Islamists and jihadists like Fateh al-Sham Front, which changed its name from Al-Nusra Front after breaking ties with Al-Qaeda.
Under the truce deal negotiated by Moscow and Washington, which came into force on Monday evening, fighting is to halt across the country except in areas where jihadists are present.
Observers have noted that the deal will be particularly difficult to implement in areas where Fateh al-Sham has formed strong alliances with local rebels, like in Idlib province.
A video posted online by activists in Khan Sheikhun showed two columns of white smoke emerging from a neighbourhood of concrete buildings.
More than 300,000 people have been killed since Syria's conflict started in March 2011 and millions have been forced to flee their homes.
The new truce deal is the latest effort to put an end to the unrest, which began with anti-government protests but has since evolved into a multi-front war that has drawn in world powers.