DAMASCUS, July 5 (Xinhua) -- The U.S.-backed Syrian Democratic Forces (SDF) advanced in the old city of Syria's northern city of Raqqa amid intense battles with the Islamic State (IS) group, a monitor group reported on Wednesday.
The U.S.-backed SDF broke the first defense line of the IS group in the old city of Raqqa, and pushed deep into that part of the city with the help of the U.S.-led coalition, said the Syrian Observatory for Human Rights.
The UK-based watchdog group said intense battles have been raging since Tuesday between the SDF, which is led by the Kurdish YPG group, and the IS militants in Raqqa. It added that the SDF advanced 200 meters inside the old city of Raqqa.
The progress by the SDF comes as the IS militants launched counter offensives in Raqqa to restore areas they lost to the SDF during the later wide-scale attack to dislodge the terror-designated group from its capital in Syria.
The Observatory, which says it relies on a network of activists group, said IS succeeded to retake some positions in the Souk al-Hal marketplace.
The raging battles over the past 48 hours killed 21 IS militants and five SDF fighters.
Meanwhile, the SDF said Wednesday that its fighters stormed the walls of the old city, adding this area is the most fortified part by IS.
The SDF, however, contributed this achievement to the help of the U.S.-led coalition, saying the U.S.-led strikes supported the SDF in their push toward the old city by opening two small passages in the walls of the old city.
The IS militants used the historic walls of the old city as a defense lines, planting the area with explosives to hinder the progress of the SDF, the group said.
It added that the U.S. coalition provided the SDF fighters with new armored humvees as well as "advanced weapons and military gears" to defeat IS in Raqqa.
Additionally, 200 fighters have joined the SDF in the fight on IS in Raqqa, said the SDF.
The SDF forces also killed 50 IS militants on Wednesday, adding that the terror group can either surrender or die.
The IS militants are fleeing in the face of the SDF attack, leaving behind large quantities of weapons and explosives.
The SDF announced the beginning of the battles to liberate Raqqa province on November 6, 2016, capturing areas in the countryside of Raqqa to isolate IS.
But June 6 this year marked the intrusion part of the battles into the heartland of IS in the city of Raqqa, which was self-declared by IS as its de facto capital in 2014.
Since then, the SDF succeeded to capture key areas on the western and eastern flanks of the city, and recently laid full siege on all exits.
