Intensified airstrikes across northern Syria by the US-led coalition and clashes on the ground have killed at least 78 Islamic State fighters since Sunday, according to a UK-based group monitoring the war.
The 78 IS militants died as they engaged in violent clashes with Kurdish People's Protection Units (YPG) fighters, the Syrian Observatory for Human Rights reported.
The air raids are some of the most sustained since these began in September, according to US officials who say they are aimed at curbing the militants' ability to operate out of Raqqa and to prevent IS fighting back against Kurdish advances.
Backed by coalition airstrikes, the Kurdish YPG fighters recaptured more than 10 villages seized by IS north of its de facto capital of Raqqa, the Syrian Observatory for Human Rights said.
YPG fighters Tuesday entered the city of Ayn Isa from the western side and clashed with IS fighters, who a day earlier launched a violent attack on YPG positions that enabled them to overrun the city and several villages in northeastern al-Hasakah province and in al- Raqqa , the monitor said.
