ISIS
ISISReuters

Fighting against the Islamic State (ISIS) group in its last enclave in eastern Syria "is going very well," a US official said Saturday, according to The Associated Press.

Spokesman for the US-led Coalition Col. Sean Ryan's comments came a day after the US-backed Syrian Democratic Forces (SDF) captured the town of Hajin, the largest urban area controlled by ISIS in the enclave.

Ryan said ISIS still poses a threat and its fighters are regrouping, planting improvised explosives devices to slow the progress of SDF offensives.

He added that the "end days" of ISIS in the enclave they hold near Iraq's border are getting closer, however, "they still have the capability for coordinated attacks, and the fight is not over."

ISIS overran large swathes of Syria and neighboring Iraq in 2014, proclaiming a "caliphate" in land it controlled.

Since then, several military offensives, including those backed by the US-led coalition, have since seen ISIS lose most areas it once controlled, including the loss of their de facto capital Raqqa in Syria..

The Britain-based Syrian Observatory for Human Rights said on Saturday SDF fighters are removing explosives in Hajin and fortifying their positions amid fighting on the eastern outskirts of the town.

The US-backed SDF has been trying to take the enclave since it launched an offensive on September 10. Since then, 932 ISIS gunmen, 545 SDF fighters and scores of civilians have been killed in the area, said the Observatory.