The self-proclaimed Islamic State of Iraq and Sham (ISIS) militants on Tuesday launched a surprise attack seizing a district of the Syrian border town Tal Abyad, which was recently taken by U.S.-backed Kurdish forces, while Assad forces retook a district in a northeastern city just days after it was captured by the militants, activists and Syrian state television reported.ISIS fighters attacked Tal Abyad on the Turkish border on Tuesday afternoon, entering from the east, according to Rami Abdurrahman, head of the Syrian Observatory for Human Rights, and Kurdish activist Mustafa Bali. Fierce battles raged for up to three hours before the ISIS fighters took shelter in an empty school building, Bali told The Associated Press by telephone.Kurdish forces drove ISIS fighters out of Tal Abyad earlier this month, depriving the group of a key point for bringing supplies and foreign fighters into Syria. The loss has already been felt in areas under ISIS control in Syria, with residents reporting a spike in the price of food and other goods.In the city of Hassakeh in Syria's remote northeast, government troops and allied paramilitary National Defense Forces regained control of the neighborhood of Eastern Ghoweiran on Tuesday, according to state television.The ISIS group last week attacked several of Hassakeh's government-held southern neighborhoods and fighting has continued since, leaving dozens dead and forcing at least 60,000 residents to flee, according to activists and a western aid group.Turkey-based opposition figure Mustafa Osso said ISIS captured a total of three predominantly Arab neighborhoods in Hassakeh last week and that fighting was continuing in the city.The U.S. military said Tuesday that the U.S.-led coalition had conducted seven overnight airstrikes near Hassakeh, hitting five groups of ISIS fighters, destroying four vehicles, an armored personnel carrier and a tank.Until the latest ISIS push, which began June 25, the predominantly Kurdish city was split between government forces and Kurdish fighters, who have been fighting the ISIS separately.In Syria's eastern province of Deir el-Zour, meanwhile, ISIS fighters have beheaded two women they accused of practicing sorcery, according to Abdurrahman of the Observatory, a monitoring group which gathers information from a network of activists inside Syria.He said one of the women was beheaded along with her husband. The beheadings were carried out over the past week, he said, without giving further details.ISIS, which controls territory in Syria and Iraq, has in the past beheaded dozens of people for blasphemy, sorcery and espionage. The group has beheaded female Kurdish fighters, but beheading civilian women remains rare.