"About 45 percent of the city is under control of the Syrian Democratic Forces," Dillon told reporters. "We estimate less than 2,000 Daesh fighters still remain in Raqqa."
The spokesperson noted that the Syrian Democratic Forces that lead the Raqqa offensive are meeting stiff, sporadic resistance from Daesh fighters entrenched in the city.
Raqqa has remained under the control of the Islamic State since 2013. The operation to liberate the city was launched by the Kurdish-Arab Syrian Democratic Forces, supported by the US-led international coalition, in early June.