(CNN) -- Syrian rebels and an al-Qaeda-affiliated group have captured a government air base near the key city of Aleppo, an opposition group said. "Early dawn today, the Islamic State in Iraq and Syria and some rebel battalions took full control of the Menagh air base," the London-based Syrian Observatory for Human Rights (SOHR) said Tuesday. "The start of this new offensive started yesterday when two non-Syrian nationals blew themselves up in an armored vehicle in front of the command center of the Menagh air base," the group added. The SOHR said one suicide bomber was a Saudi Arabian. Fighters from the Islamic State of Iraq and Syria and various rebel battalions destroyed several tanks and killed a number of regime soldiers, the observatory said. At least 10 rebel fighters, including foreigners, were also killed, the group added
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New: A car bomb blast in southern Syria kills 18 people, including three children
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The Menagh air base is near Aleppo, Syria's largest city and financial hub
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For many months, rebels have tried to wrest control of Aleppo in the country's civil war
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The Islamic State of Iraq is the rebranded name for al Qaeda in Iraq
The Syrian regime downplayed reports that opposition fighters -- whom it calls "terrorists" -- had taken over @placeholder air base.