Damaged buildings are seen at al-Amriya frontline in Aleppo.  Picture taken from a rebel-held area.  Reuters

Reuters/Beirut

Dozens of members of the Syrian security forces and insurgent fighters were killed on Wednesday in an attack on a government security building in the northern city of Aleppo, a group monitoring the civil war said.
The Syrian Observatory for Human Rights, which tracks the violence using sources on the ground, said initial reports indicated the insurgents had started the attack by blowing up a tunnel dug near or under the Air Force Intelligence building.  The rebels then launched an attack on the building.

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