Osman Orsal / Reuters
Smoke rises over the Syrian border town of Azmarin during clashes Friday between the Syrian army and rebels.
BEIRUT -- Syrian rebels captured an air defense base east of the key city of Aleppo on Friday as government forces battled insurgents on several fronts across the country, anti-regime activists said.
Clashes were also taking place at a military barracks close to Maarat al-Nuaman, a town on the main highway to Aleppo that was seized by rebel forces earlier this week, the U.K.-based Syrian Observatory for Human Rights said.
Aleppo, in the northwest of the country, is Syria's largest city and commercial hub. It has been fiercely contested since July.
The pro-opposition Observatory gave a death toll for Thursday of more than 260 people, including civilians and combatants on both sides in violence in the capital and the north, west and east.
It said 92 soldiers were killed on Thursday, which would be one of the highest daily casualty counts on the government side since the uprising against President Bashar Assad broke out in March 2011.
The official SANA news agency also reported fighting nationwide and said dozens of rebels, which it called "mercenary terrorists," had been killed.
The reports could not be independently verified. If true, however, they indicate a rapidly intensifying conflict, with the death tolls of the past several weeks far exceeding previous months.
Clashes on the border with Turkey
Although international attention has focused on the Turkish border in the past week, Aleppo and the city of Homs -- north of Damascus and near the border with Lebanon -- are being fought over and clashes take place almost daily in the suburbs of the capital Damascus as well as in the countryside.
Turkey scrambled two fighter planes to the border with Syria on Friday after a Syrian military helicopter bombed the Syrian border town of Azmarin, according to a Reuters witness.
Fighting along Turkey’s 560-mile border with Syria has repeatedly spilled over into Turkish territory in the past week, with the Turkish army responding in kind to gunfire and mortar shells fired from Syria.
Turkish Chief of Staff Gen. Necdet Ozel said Wednesday his troops would respond "with greater force" if the shells continued to land on Turkish soil, and parliament last week authorized the deployment of troops beyond Turkey, heightening fears that Syria's civil war will drag in regional powers.
Jihadi group reportedly takes part in base assault
The Observatory said the air defense base seized by the rebels was located in al-Tana village by the Koris military airport on the road east from Aleppo to al-Raqqa.
Videos posted online Friday claiming to have been shot inside the base said the extremist group, Jabhat al-Nusra, participated in the battle, according to The Associated Press. The videos show dozens of fighters inside the base near a radar tower, along with rows of large missiles, some on the backs of trucks.
A report by a correspondent with the Arabic satellite network Al-Jazeera who visited the base Friday said Jabhat al-Nusra had seized the base. The report showed a number of missiles and charred buildings, as fighters covered their faces with black cloths.
Two Aleppo-based activists and Rami Abdul-Rahman, head of the Syrian Observatory for Human Rights, also said Jabhat al-Nusra fought in the battle.
Little is known about Jabhat al-Nusra, or the Support Front, which began claiming attacks in Syria earlier this year in postings on jihadi forums often used by al-Qaida. While neither group has officially acknowledged the other, analysts say al-Nusra's tactics, jihadist rhetoric and use of al-Qaida forums point to an affiliation.
Western powers -- and many Syrians-- worry that Islamist extremists are playing an increasing role in Syria's civil war.
Highway route cut
Meanwhile, the capture of Maarat al-Nuaman cut the highway between Aleppo and Homs, the main route for the government to resupply and reinforce the northern city.
SANA said government forces were mounting operations to clear rebels from Aleppo's Karm al-Jabal area on Friday.
More than 30,000 people have been killed in the conflict, which began as a popular uprising against four decades of Assad family rule before descending into civil war. The armed forces have relied heavily on air power and artillery to hold back the rebels.
Fighting has also spilled over the borders into Turkey, Lebanon, Jordan and the Israeli-occupied Golan Heights, raising concern that the fighting could spread across the region, now home to 340,000 Syrian refugees.
Reuters and The Associated Press contributed to this report.
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