DAMASCUS, Nov. 30 -- At least 50 Islamic State (IS) militants were killed over the weekend during the strikes by the U.S.-led anti-terror coalition and clashes with Kurdish militants near the border with Turkey, a monitoring group reported Sunday.

The 50 fighters were killed during clashes on Saturday in the predominantly Kurdish city of Ayn al-Arab, also known as Kobane, in northern Syria on the borders with Turkey, the Syrian Observatory for Human Rights said, adding that the death toll includes five IS fighters who blew themselves up.

The border crossing between Ayn al-Arab and Turkey also witnessed clashes between the Kurdish People's Protection Units (YPG) and IS fighters, the Observatory said, adding that the clashes actually took place on the Turkish side of the borders, prompting the Turkish border guards to demand the YPG to return to the Syrian side.

It said the Turkish authorities recaptured the border crossing and another area nearby known as al-Sawame, and that the YPG advanced southwest of Ayn al-Arab toward the edges of the Syrian city of Aleppo.

The Observatory, which relies on a network of activists on ground, said IS militants fired some 160 mortar shells into Ayn al-Arab on Saturday.

The IS unleashed its wide-scale offensive against Ayn al-Arab on Sept. 15 in a bid to capture the city, which would enable the IS to link its self-declared capital of al-Raqqa province with Ayn al-Arab and stretch its territory to areas bordering Turkey.

The IS has captured hundreds of small villages around the city and managed to storm parts of it, after forcing over 160,000 people to flee toward neighboring Turkey.