An explosive-laden vehicle was detonated at the checkpoint when it was detected by military personnel, Xinhua news agency reported.
Another suicide bomber detonated his explosive belt amid the crowd which gathered to help those injured in the first blast.
Both bombers, wearing military uniforms, were disguised as government troops, the military said.
Also on Monday, a third car bomb went off at a checkpoint at the entrance of al-Zahara neighbourhood in Homs province.
In the capital Damascus, an explosion took place near the resort town of Sabura while an explosive-packed motorcycle detonated in the predominantly-Kurdish city of Hasakah.
However, it was not immediately known if the bombings, one day after government forces' recaptured key military targets from rebels in Aleppo province in Syria, were coordinated.
