A Turkish drone targeted a sponge factory near the village of Shamuka, between the towns of Hasaka and Tel Tamr, killing three SDF members, activist Jasim Alyan told The New Arab's Arabic-language sister site, Al-Araby Al-Jadeed.
The Rojava Information Centre said two SDF soldiers were killed in shelling in Istirahat Wazir, also located between Hasakeh and Tel Tamr, on Thursday night.
The strikes preceded a deadly rocket attack on the city of Al-Bab on Friday, which killed 14 civilians and injured 35 more and came from an area held jointly by the SDF and the Assad government.
Istirahat Wazir has reportedly been a base for the US-led international coalition in Syria, which cooperates with the SDF. The Syrian Observatory for Human Rights (SOHR) said the sponge factory and Istirahat Wazir base are located close together.
SOHR said two SDF members were killed in the strike but the SDF has yet to officially confirm any casualties.
The SDF said however that they had killed seven Turkish soldiers in strikes on areas near the Turkish-Syrian border, according to The New Arab's affiliate Syria TV.
Syrian state-affiliated media said a regime soldier was killed in a Turkish drone strike close to the town of Abu Rasin in Hasakeh province.
Damascus said Wednesday that three of its soldiers had been killed in Turkish bombing close to the town of Kobane.
After months of threatening to undertake a large-scale operation in northern Syria, Turkey and its local allied forces carried out several attacks across northern Syria this week. Turkish troops have also moved across the border into Syria.
However, Turkish interior minister Suleyman Soylu said Tuesday evening that Turkey's actions served only as a "small warning".
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