At a house in Aleppo\'s old city, shaken by the thud of incoming artillery, Syrian rebels load their Kalashnikovs and prepare for battle. After traditional midday prayers their cry -- Allahu Akbar (God is greatest) -- pierces the air as shells slam down and fighter jets bomb rebel positions in the strategically crucial northern city. In a flash, the men disappear, rushing off to their designated front line in a motorcade of cars and mini vans. \"Today we are raiding the Hanano military base because there are a lot of army soldiers, snipers and shabiha (pro-regime) mercenaries there,\" says Abu Omar, a field commander of the opposition Free Syrian Army. \"Several brigades are taking part in this offensive,\" he told AFP, standing in a covered alley way. Fighting escalated in the city of Aleppo when opposition fighters launched an attack against a military base while war planes and artillery pounded areas under their control. Commander Omar says the goal of the new offensive is to liberate Hanano, cut strategic supply lines and put a stop to shelling attacks that have caused high civilian casualties in the commercial city. FSA media coordinator Abdullah Yasser says the assault aims to take down one of three main positions used by the army to shell rebel-held areas concentrated in the east of Aleppo. \"Hanano is one of the main places from which they are shooting so taking it over could be a turning point for us,\" he tells AFP. Yasser stressed that a lot of planning has gone into the operation, that more than 100 men were taking part and that they will not turn back no matter how many lives are lost. Panic gripped the streets in the afternoon, as drivers zoomed past the citadel and the roundabout of Al-Shaar in a bid to avoid sniper fire and aerial attacks. Few people walked the streets and many darted across intersections as an added precaution. Those who were out in the open kept their eyes on a fighter jet flying low, and directed traffic out of harms way. \"Turn back, turn back!\" shouted a falafel vendor to a taxi driving straight into a roundabout under fire. At around 3:00 pm (1200 GMT) the first batch of vehicles packed with wounded and shell-shocked fighters returned from the front line. Those worst injured lay on stretchers screaming, their blood dripping all over the hospital floor. Men with superficial injuries limped out of the way of frazzled nurses. One man, unable to find a stretcher, lay in agony in the entrance hall. \"They shelled us in Hanano,\" said an FSA fighter with bloodshot eyes. A nurse at the clinic said \"artillery fire and air strikes left dozens of civilians wounded\" on Friday but refused to release figures of fighter casualties because this is \"bad for morale.\" In a corner, a woman holding two children whose faces were nicked by shrapnel, wept uncontrollably. \"I don\'t know where their mother or where my husband is,\" she wailed, dialing frantically on her phone only to find the network down. The FSA\'s surprise attack came after a night of close quarter gun battles in the old city, AFP journalists at the scene said. \"They have been intensifying their attacks because no one in the international community has stepped up to defend the Syrian people,\" Abu Omar charged.