Fierce fighting erupted in several districts of the northern Syrian city of Aleppo on Sunday as regime troops tried to storm the rebel-held neighbourhood of Salaheddin, a monitoring group said.
Sunday's clashes raged a day after opposition forces repulsed an offensive by government troops in the city, said the Britain-based Syrian Observatory for Human Rights.
"There are clashes on the edges of the (southwest) district of Salaheddin," Observatory head Rami Abdel Rahman said.
"Regime forces are also using helicopters to pound the district. Fighting is also happening in the central neighbourhood of Bab al-Hadid."
Abdel Rahman described the situation in Aleppo as ‘a full-scale street war,’ with fighting in the Sukari, Fardoss and Jisr al-Hajj neighbourhoods.
Clashes were also reported on Sunday morning in Zahraa, Arkub and Al-Hindrat Camp, the Observatory reported.
Rebel forces broke into a juvenile detention centre, said Abdel Rahman, ‘in order to set the prisoners free.’
Families displaced by the fighting in Aleppo were having difficulty finding refuge ‘because nowhere is safe any more,’ he added.
In the central city of Homs, a battle broke out near the police headquarters between troops and rebels, at least one of whom was killed. In the same city, regime forces "violently shelled" the rebel-held district of Khaldiyeh, which has been under siege for almost 60 days.
Near the capital, sniper fire killed a civilian in the town of Irbin, the Observatory said. Three more people were killed in shelling in Idlib province in the northwest.
Near Douma, in Damascus province, a rebel fighter was shot dead.
By Sunday afternoon, the Observatory had reported a total of seven killed across Syria: four civilians and three rebels.
On Saturday, violence killed 168 people - 94 civilians, 33 rebels and 41 soldiers, the Observatory said.
More than 20,000 people have died in Syria since the uprising against President Bashar al-Assad's rule broke out in March last year, according to the watchdog's figures.
It is not possible to check casualty tolls independently in Syria. The United Nations has a troubled military observer mission in the country but has stopped giving figures for the overall death toll.