Syrian warplanes pounded a strategic northern city with three airstrikes Tuesday as ground troops pushed forward to recapture the area recently taken by rebels, activists said. The fighting over Maaret al-Numan, which sits along the main highway that connects Aleppo and Damascus, comes as the regime intensifies efforts to retake the area that was seized by rebels earlier this month. Their presence has disrupted the regime's ability to send supplies and reinforcements to Aleppo, where regime forces are bogged down in a bloody fight for control of the country's largest city. Syrian troops have been fighting against rebels in Aleppo since July and rebel advances over the past week have added urgency to the battle. The Britain-based Syrian Observatory for Human Rights said four people, including three young girls, were killed in the air raids on Maaret al-Numan. Another activist group, the Local Coordination Committees put the death toll from the airstrikes and ground fire at 19. Discrepancies in casualty tolls are frequent because of restrictions on independent reporting and the chaos on the ground. The LCC and the Observatory reported air raids on several suburbs of Damascus including the restive areas of Arbeen, Zamalka and Douma.