The Britain-based Syrian Observatory for Human Rights and the Aleppo Today TV station say the ISIS extremists captured al-Rai early on Monday morning after intense fighting for the frontier town.
Al-Rai is strategically located on the border with Turkey, serving as ISIS' access point to supply lines. It also sits along the road to the ISIS stronghold in Aleppo province.
ISIS lost the town on Thursday after an offensive by rebels and militant groups allied with them, including Al-Qaida's branch in Syria known as the Nusra Front.
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