At least 40 people were killed and 170 were injured in two explosions that rocked a highway near the capital, Damascus on Thursday, Al Arabiya reported.
According to the reports broadcast by the Syrian TV, the blasts, which were followed by a skirmish, went off near the highway, leading to the airport, reportedly targeting Syrian security services.
Most of the dead are believed to be civilians, with the explosion occurring during the morning rush hour. Footage taken in the aftermath of the blast shows a burnt bus and dozens of wrecked cars, some with bodies still inside them.
The explosions came just a day after a roadside bomb struck a Syrian military vehicle in Deraa, only seconds after a car carrying Norway’s Maj. Gen. Robert Mood, head of the U.N. observer mission in Syria, had passed by.
The explosions occurred amid a ceasefire, which formally came into force in Syria on April 12, as a part of a plan proposed by the U.N. and Arab League envoy, Kofi Annan.
A 30-strong observer team arrived in Syria on April 15 to monitor the shaky truce between the government and opposition. The monitor mission will later be expanded to 300 peacekeepers.
The Foreign Ministry in Moscow denounced the bloody attack while saying that the blasts should not be allowed to prevent the UN observers, who include Russian representatives, from carrying out their mission.
According to UN estimates, more than 34 children have been killed in Syria since the ceasefire was implemented.
More than 9,000 people have been killed in Syria since the outbreak of a popular uprising against President Bashar al-Assad in March, 2011, the UN said.
Moscow has twice vetoed U.N. Security Council resolutions over what it called a pro-rebel bias since the start of the uprising against Assad, but has given its full backing to the Annan peace plan.