attacks accounted for tens of thousands of injury last year. the observatory for human rights reports more than 6,500 syrians were killed by air strike. half of those happened in aleppo. the group reports 40,000 people were wounded across the country and many of them now permanently disabled. cnn has obtained footage right from the front heens. and all this week we're bringing you reports from the city. this shows how a battle could determine its feat. >> reporter: in the abandoned mansions a battle for the biggest city is reaching the peak. this is just outside aleppo. the village, key to the last remaining supply line for rebels into the city.