Lefteris Pitarakis, Associated Press
In this Monday, June 15, 2015 file photo taken from the Turkish side of the border between Turkey and Syria, in Akcakale, southeastern Turkey, Kurdish fighters with the Kurdish People's Protection Units, or YPG, wave their yellow triangular flag in the outskirts of Tal Abyad, Syria.

BEIRUT — Islamic State fighters on Tuesday launched a surprise attack on a Syrian border town recently seized by U.S.-backed Kurdish forces, while Syrian government forces retook a district in a northeastern city just days after it was captured by the militants, activists and Syrian state television reported.

IS 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 IS fighters took shelter in an empty school building, Bali told The Associated Press by telephone.

Kurdish forces drove IS fighters out of Tal Abyad earlier this month, depriving the extremist group of a key point for bringing supplies and foreign fighters into Syria. The loss has already been felt in areas under IS 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 IS 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 IS 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 IS fighters, destroying four vehicles, an armored personnel carrier and a tank.

Until the latest IS push, which began June 25, the predominantly Kurdish city was split between government forces and Kurdish fighters, who have been fighting the IS separately.

In Syria's eastern province of Deir el-Zour, meanwhile, IS 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.

The IS group, which governs its self-styled caliphate in accordance with an extreme interpretation of Islamic law, 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.

Associated Press writer Bassem Mroue contributed to this report.