The Syrian Democratic Forces (SDF), a group of Kurdish and Arab fighters backed by the U.S., have captured a number of key neighborhoods near Raqqa, an ISIS stronghold in Syria, the group announced Monday. The announcement signals the progress of a larger offensive, launched last week, to overtake Raqqa from ISIS militants, who have maintained control of the city since 2014. In May, the Trump administration offered critical assistance by agreeing to arm and train members of the SDF’s primary Kurdish militia, the People’s Protection Units (YPG).

In the last few days, the SDF has succeeded in carrying out attacks to the north, east, and west. On Monday, the group captured the western neighborhood of al-Romaniya and a sugar factory complex in the northeast. On the same day, the U.K.-based Syrian Observatory for Human Rights reported that SDF had overtaken the industrial neighborhood of al-Sanaa, though fighting in the area continues. According to Ahmad Mohammed, an SDF media officer, the group has now reached the walls of the Old City, a neighborhood east of central Raqqa.

A local activist group announced Sunday that coalition air strikes, backed by the U.S., have destroyed “almost every important building in Raqqa,” including schools and mosques. In the last 48 hours, at least 24 civilians have reportedly been killed due to escalating violence in the region. The SDF has previously estimated that around 3,000 to 4,000 ISIS fighters are trapped in Raqqa, along with around 160,000 civilians.