Kurdish forces on Monday seized a key rebel bastion in Syria's Aleppo province, extending the opposition's losses in the region after a major regime offensive on the area.
The Kurdish People's Protection Units (YPG) seized control of Tal Rifaat from mostly Islamist rebel forces on Monday night, according to local sources.
Activists told The New Arab that the YPG offensive coincided with intense Russian air raids on the town.
"Kurdish forces entered the town after Russian warplanes carried out over 200 airstrikes, couple by a complete blockade," said Majid Abd al-Nur, an activist from northern Aleppo province.
The YPG capture came despite Turkey shelling the town to try to halt Kurdish forces from advancing after several days of attacks on the one-time rebel stronghold.
It left the rebels in Aleppo with only a few remaining bastions, including the town of Marea, just east of Tal Rifaat, and the border town of Azaz to the north.
Elsewhere, the rebels have largely crumbled in the face of a major regime operation backed by Russian air power and the simultaneous Kurdish attack.
In recent days, the YPG seized the Minnigh airbase from rebels, and regime forces have virtually encircled the opposition-held eastern part of Aleppo city.
The opposition defeats have angered Turkey, a longstanding backer of the uprising against President Bashar al-Assad.
Ankara is particularly sensitive about the YPG advance.
It views Syria's powerful Kurdish YPG forces as affiliates of the Kurdistan Workers' Party (PKK), an outlawed group that waged a decades-long insurgency against the Turkish state.
Turkey has shelled YPG positions for the past three days and warned against an advance on Azaz, the last rebel stronghold between Turkish and Syrian territories, but so far has been unable to halt their advance.
Syria's Kurds have used the country's unrest in an attempt to build a semi-autonomous region in Kurdish-majority areas in north and northeast Syria.
Their latest advances are part of a bid to unite the Kurdish town of Afrin in western Aleppo province with Kurdish areas to the east.
Turkey is strongly opposed to the creation of a united Kurdish region along its border with Syria, and has warned that it is willing to intervene to halt the project.
Agencies contributed to this report