Reports of at least nine civilians killed and dozens wounded spread on Sunday when around one hundred mortars and rockets were fired on a mainly Kurdish residential quarter in Syria's northern city of Aleppo, the UK-based Syrian Observatory for Human Rights, which tracks violence in Syria, confirmed.
The rights group said the attack was among the biggest allegedly carried out by Al Qaeda's Syrian offshoot Nusra Front in the area, which also adjoins state-run parts of Aleppo.
Heavy fighting flared in Ashrafiyah and in the Sakan al Shabibi neighbourhoods where YPG militants sought to advance in opposition-held areas, with no signs that a deal agreed to decreased hostilities by international parties was holding in that area.
A number of Syrian opposition groups as well as the regime had agreed to decrease tensions as the international community seeks to push through a transition phase to finally end the five-year-long conflict that has ravaged the country.
However, the Nusra Front and DAESH terrorist group were not included in the talks.
The residential Sheikh Maqsoud quarter has been a major frontline in Aleppo for weeks, with heavy clashes between YPG militias and opposition fighters in control of large parts of the eastern portion of the divided city.
YPG, is the armed wing of the PKK-affiliated PYD, which seeks to impose its Marxist-Leninist ideology on mainly Kurdish areas in the region. Although the PKK is listed as a terrorist organisation by Turkey, the EU and the US, the US considers its PYD offshoot as an ally in the fight against DAESH terrorists.
Turkey on the other hand has been calling on the international community to blacklist the PYD, and accuses it of coordinating with Syrian autocrat Bashar al Assad’s regime.
The YPG has been trying to take advantage of the preoccupation of opposition fighters with fending off a regime ground offensive to disrupt traffic on the main highway that Sheikh Maqsoud overlooks used by passengers and combatants to get into the opposition held areas of the city.
The permanent closure of the main Castello highway by YPG sniper fire would cut supplies of food to hundreds of thousands of civilians and allow the regime forces to fully encircle opposition-held parts of Aleppo.
Rapid advances by the regime with the support of Russian air strikes and its Iranian-backed allies in the northern Aleppo countryside early last month allowed them to cut vital supplies lines by the opposition into Aleppo.
The YPG also made advances in that area in the wake of the progress by the regime forces.