Syrian military aircraft have been pounding Aleppo as both rebels and the government claimed advances in the disputed city.
The worst of the fighting has been centred in the Salaheddine district.
Reuters reported that neither side was in full control of the neighbourhood.
The key flashpoints are concentrated in the southwest and northeast of Syria’s commercial capital.
Over 200,000 people have fled Aleppo.Residents unable to get out are seeking refuge in schools and other public buildings, UNHCR spokeswoman Melissa Fleming said.
“There are 32 schools in Aleppo that we’ve identified and in each of those schools we have heard or witnessed that 250 to 350 people were packed inside. There are a total of some 7,000 people staying in dormitory rooms,” she said.
A rebel commander was quoted by Reuters as saying that his fighters will push towards the centre of Aleppo and take the whole city “within days, not weeks.”