BEIRUT -- Syrian warplanes and artillery blasted parts of the capital Damascus and its rebellious suburbs on Sunday, part of what activists described as intense fighting as rebels try to push their way into the center of President Bashar Assad's power base.
In central Syria, a car bomb killed at least 15 people, the official news agency reported.
The fighting over the past few weeks in Damascus is the most serious in the capital since July, when rebels captured several neighborhoods before a swift government counteroffensive swept them out.
The Britain-based activist group Syrian Observatory for Human Rights said fighter jets struck twice in the suburb of Daraya as regime artillery pounded other districts just south of Damascus.
The Syrian air force also launched airstrikes on the northern city of Aleppo, some cities in the northern province of Idlib and the Mediterranean city of Latakia, the Observatory said. The group relies on reports from activists on the ground.
The Damascus suburbs have been opposition strongholds since the uprising against Assad began in March 2011. In the past weeks, the army has pressed an offensive to regain lost territory near the capital, including two air bases.
The Observatory said there was also ongoing fighting in towns near the Damascus International Airport on the southern edge of the city. The towns include Aqraba, Beit Saham and Yalda.
The road to the airport from Damascus was closed on Thursday because of heavy fighting, but authorities reopened it after troops secured the area, activists said. The Information Ministry said on Saturday the airport was operating normally and that the road leading to the facility is "totally secure."
On Sunday, EgyptAir chief executive Roshdy Zakaria said the country's national carrier will resume flights to Damascus and Aleppo after a three-day suspension because of poor security on the roads around the two airports.