BEIRUT – Syria’s civil war is closing in on President Bashar Assad’s seat of power in Damascus with clashes between government forces and rebels flaring around the city Tuesday, raising fears the capital will become the next major battlefield in the 20-month-old conflict.

Numerous reports emerged of at least a dozen people killed, and the regime said nine students and a teacher died from rebel mortar fire on a school.

While many of the mostly poor, Sunni Muslim suburbs ringing Damascus have long been opposition hotbeds, fighting has intensified in the area in recent weeks as rebels press a battle they hope will finish the regime.

“The push to take Damascus is a real one, and intense pressure to take control of the city is part of a major strategic shift by rebel commanders,” said Mustafa Alani of the Geneva-based Gulf Research Center.

“They have realized that without bringing the fight to Damascus, the regime will not collapse.”