Activists: Kurdish fighters advance against IS group in northern Syrian town of Kobani

FILE - In this Monday, Oct. 20, 2014 file photo, thick smoke and flames erupt from an airstrike by the U.S.-led coalition in Kobani, Syria, as seen from a hilltop on the outskirts of Suruc, at the Turkey-Syria border. Kobani, also known as Ayn Arab, and its surrounding areas has been under assault by extremists of the Islamic State group since mid-September and is being defended by Kurdish fighters. (AP Photo/Lefteris Pitarakis, File) (The Associated Press)

Iraqi Kurdish forces tow a howitzer near the front lines on their way to the city of Sinjar, as the Kurdish peshmerga fighters move through Zumar, Iraq, Friday, Dec. 19, 2014. Sporadic clashes between Iraqi Kurdish fighters and Islamic State extremists, as well as other logistics problems, are delaying the evacuation of the last Yazidis still trapped on Sinjar mountain, an Iraqi lawmaker said Friday. (AP Photo/Zana Ahmed) (The Associated Press)

Iraqi Kurdish forces throw victory signs, as they drive near the front lines in Zumar, Iraq, Friday, Dec. 19, 2014. Sporadic clashes between Iraqi Kurdish fighters and Islamic State extremists, as well as other logistics problems, are delaying the evacuation of the last Yazidis still trapped on Sinjar mountain, an Iraqi lawmaker said Friday. (AP Photo/Zana Ahmed) (The Associated Press)

A Kurdish official and an activist group say Kurdish fighters have advanced in the contested northern Syrian town of Kobani after heavy clashes with the Islamic State group.

Nawaf Khalil, a spokesman for the Kurdish Democratic Union Party, says Kurdish fighters advanced Saturday in six neighborhoods and have besieged the IS-held Cultural Center east of town.

The Britain-based Syrian Observatory for Human Rights says the main Syrian Kurdish force, known as the People's Protection Units, or YPG, killed several IS fighters.

The IS group began its Kobani offensive in mid-September, capturing parts of the town as well as dozens of nearby villages.

Kurdish forces have gradually pushed the extremist group back in recent weeks with the help of U.S.-led coalition airstrikes.