Kurdish fighters seized a key town in northern Syria from the Islamic State group on Monday, cutting a supply lifeline from the jihadists' de facto Syrian capital, a monitor said.
"The Kurdish People's Protection Units (YPG) took full control of Sarrin on Monday after three weeks of intense clashes," said Rami Abdel Rahman, head of the Syrian Observatory for Human Rights.
Sarrin lies along the M4 highway, which IS uses to transport fighters and supplies between Aleppo province and the group's de facto Syrian capital of Raqa in the east, Abdel Rahman said.
The town's capture cuts off IS's main access route to parts of Aleppo province, where the jihadists are fighting both Kurdish forces and rebel groups.
"Sarrin was also used as a base for IS to attack the Kurds in Aleppo province, so those attacks will probably decrease as well," he told AFP.
Signup to our newsletter and follow us on Facebook and Twitter!
Mustafa Ebdi, a Kurdish activist from the flashpoint town of Kobane some 40 kilometres (25 miles) north of Sarrin, said the YPG were still combing through the town to clear it of potential IS suicide bombers.
YPG forces began their offensive on Sarrin on July 6 with air support from the US-led coalition fighting IS in Syria and Iraq.
The capture of the town, which lies on the east bank of the Euphrates river, is the latest victory for Kurdish forces in Syria against IS.
They defeated IS forces in Kobane in January, expelling them with the help of coalition air strikes.
And on June 16, they pushed IS out of Tal Abyad, a town on the Syrian-Turkish border used by IS to bring in weapons and fighters to Raqa.
The Syrian conflict began with anti-government protests in March 2011, but has developed into a multi-front civil war involving Kurds and jihadists of both IS and Al-Qaeda, as well as other rebels and regime loyalists.