A bomb dropped by the Syrian military on Thursday struck a gas station in the country's north, killing at least 50 people and leaving dozens wounded, the Washington Post reported.
Reports of the final death toll from the bombing varied, ranging from 30 to some counts as high as 150. The Telegraph reported 54 dead in the village of Ain Issa in what would be, if confirmed, "the deadliest single air strike of the country's civil war."
NBC and wire services reported that hundreds may have died across Syria in air strikes on Thursday. NBC reported that there has been a "marked escalation in air attacks by forces loyal to President Bashar Assad," according to the British-based Syrian Network for Human Rights.
Citing opposition activists, the Post said that the bombing may have been a retaliatory measure after rebel fighters successfully took control of a border crossing with Turkey on Wednesday.
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A correspondent from a Syrian opposition news network said, "It’s a massacre," according to the Post.
Video said to have been obtained by the Post from the Ugarit News, also released by the Associated Press, showed the aftermath of the gas station bombing, with thick black smoke rising from damaged and destroyed vehicles.
"The only reason why [the regime] would strike the petrol station with a jet is to kill the highest number of people possible," an activist told the Telegraph.
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The Syrian government is increasingly attacking from the air in its fight against the rebels, with activists saying the air strikes have turned parts of Damascus into a disaster zone.
GlobalPost's correspondent in Syria, Tracey Shelton, reports that the Free Syrian Army is planning to target civilian airports, with the rebels saying they have been left with little choice.
"Facing a near constant barrage of regime attacks from the air, and little support from the international community to enforce a no-fly zone, the rebels are attempting — on their own — to cripple the government’s ability to launch airstrikes and move weapons," Shelton writes.
The UN estimates that the 18-month-old conflict in Syria has left at least 20,000 people dead.