One air strike hit a rebel-held area near the capital Damascus, while another one hit a prison in Idlib province.
At least 32 people have been killed as a result of air strikes in two different locations in war-torn Syria, a war monitor said on Saturday.
In the latest incident, 16 civilians were killed and dozens wounded in an air strike on a rebel-held area outside the capital Damascus, the Syrian Observatory for Human Rights said.
It said it was not immediately clear who was responsible for the strike on the town of Hammuriyeh in the opposition bastion of Eastern Ghouta, which has been targeted by both the Syrian regime and its ally Russia in the past.
"Sixteen civilians, including a child, were killed and around 50 others wounded in an air strike on the main street in the town of Hammuriyeh," Observatory director Rami Abdel Rahman said.
He could not immediately confirm if all the wounded were civilians, or if some were rebels.
The death toll could rise further because a number of the injured were in serious condition, he added.
The Eastern Ghouta region outside Damascus has been under a devastating government siege since 2012, and is also the regular target of regime air strikes and artillery fire.
Idlib prison hit
Another 16 people died late Friday night in an air strike on a prison in Syria's rebel-held Idlib province in northwest Syria, the Observatory said on Saturday.
Idlib is a key rebel stronghold that includes militant factions who seek to overthrow regime leader Bashar al Assad.
The regime air force, backed by Russia, has been heavily bombarding rebel positions.
The Observatory said it had received information that some of those who died were shot dead while attempting to flee the prison after the air strike hit one side of it. Two jailers were among the 16 people killed.
The population of Idlib has been swelled by refugees, including many of those who have left rebel-held enclaves elsewhere in the country after the regime army and its allies forced them to surrender.
While parts of Idlib are controlled by Turkey-backed rebels, including factions who fight under the banner of the Free Syrian Army, other areas are dominated by the hardline Ahrar al-Sham and others by the Tahrir al-Sham militant alliance.
Tahrir al-Sham's strongest component is the former Nusra Front group which was Al Qaeda's official branch in Syria until last year, when it broke formal ties with the global organisation.
UN calls for ceasefire talks
Russia, Iran and Turkey need to convene more Syrian ceasefire talks as soon as possible to bring the situation on the ground under control, UN Syria envoy Staffan de Mistura said on Friday.
De Mistura is mediating political talks in Geneva, while a separate series of talks in the Kazakh capital Astana — arranged by Russia, Iran and Turkey — is supposed to guarantee the ceasefire.
The UN envoy said he had made a strong suggestion "that they do retake the situation in hand and hopefully there will be an Astana meeting as soon as possible in order to control the situation which at the moment is worrisome".
While the ceasefire talks have made no ground, a first round of political talks in Geneva was procedural, producing only an agenda for the current round, which will encompass four topics: a new constitution, new elections, reformed governance and the fight against terrorism.