The capture of Azaz puts the Islamic State of Iraq and Syria less than a mile from the Bab al-Salameh border crossing, which has been under opposition control for more than a year. The crossing remains under FSA control after rebels sent reinforcements, including heavy weapons and tanks, said Abu Mahmood Marei, an activist at the crossing.
The Islamic State of Iraq and Syria, which at turns fights alongside and against mainstream rebels, attacked the hospital in Azaz in an attempt to detain a German doctor who was working there, said Marei, who went to the town earlier in the day. It was unclear what charitable organization the doctor was affiliated with. Some activists reported the hospital is run by Doctors Without Borders, but a spokesman for the organization denied this.
"They are extremists," Marei said of the Islamic State. "This doctor is coming to help us, to give us medicine and treat us, but they consider him an infidel."
Fighters with the Northern Storm Brigade defended the hospital and clashes erupted, leaving several civilians and fighters dead, Marei and others said. A local activist, Hazim Azazi, attempted to broker a truce but was shot by a sniper with the Islamic State, Marei said.
The Al Qaeda group prevented Azazi from being taken to the hospital and he bled to death, Marei said.
Within hours, the Islamic State seized control of the town, including the hospital, where it detained the doctors, said Mamoon Khateeb, an activist in nearby Marea. The group also attacked rebel checkpoints along the outskirts of the town and seized those as well, he said.
Islamic State fighters have been in Azaz for some time and have gradually tried to control all aspect of the town, including its centers and mosques, Khateeb said.
A statement released earlier in the day and posted on Northern Storm's Facebook page called on Al Tawheed Brigade, one of the largest rebel groups in Aleppo province, which has strong relations with both the FSA and Islamist groups, to protect the town and "liberate it from the brigades of [Islamic State], which is killing civilians and raiding their homes." Al Tawheed Brigade provided the reinforcements to keep the border crossing under FSA control.
Abu Firas Halabi, a spokesman with Tawheed, said the brigade was waiting for the situation to calm down before it tried to mediate the situation peacefully.