The US-backed Syrian Democratic Forces (SDF) drove out the Islamic State (IS) from two establishments in the northern countryside of Deir al-Zour province in eastern Syria on Saturday, Kurdish activists said.

The Kurdish-led SDF captured the electricity station and the sugar factory in northern Deir al-Zour after defeating the IS militants, activists said.

The new progress comes as the SDF, an alliance of Kurdish, Arab and Assyrian fighters led by the US coalition and the Kurdish YPG group, declared a battle on IS in the northern and eastern countryside of Deir al-Zour last Saturday.

Fighting separately in Deir al-Zour, the Syrian army continued to advance in the capital city of Deir al-Zour and its suburb, capturing the area in the southern countryside of Deir al-Zour, following battles with IS, according to state news agency SANA.

The SDF forces are fighting in the northern and eastern countryside of Deir al-Zour as part of the US plan to have an area of influence east of the Euphrates River, near the Iraqi border.

The Syrian army, meanwhile, is focusing its attention on driving out IS from the 35 percent of areas they are controlling in the capital city of Deir al-Zour, just 10 days after breaking IS’ three-year siege on the city with the help of Iranian-backed fighters and the Russian air force.

Earlier on Saturday, Kurdish activists said Russian or Syrian warplanes struck SDF positions east of the Euphrates River, wounding eight SDF fighters.

Later, Sebyan Hamo, a spokesman of the YPG, said: “we will liberate all those areas from IS and whoever tries to hinder our progress or attack us will receive our retaliation.”

“We demand a clarification from Russia about the reasons behind hitting our forces,” he continued.

The SDF and the Syrian army are fighting IS separately, and even though they haven’t come to clash with one another, both don’t seem on the same page.

The SDF has already been advancing in the northern city of Raqqa, the de facto capital of IS, capturing over 70 percent of the city with the help of the US-led coalition.

While IS is the target, a possible confrontation between the SDF and the Syrian army doesn’t seem impossible, but brewing until the final IS defeat.

Syrian officials repeatedly said that they will liberate all Syrian cities, hinting that even the areas under the SDF control will be retrieved.