Nine Russian air strikes have hit hospitals or field clinics operating in war-torn Syria, killing civilians and medical staff, a Syrian medical organization said late Thursday.

The Syrian-American Medical Society, which operates several facilities in Syria, said a deadly strike earlier this week “adds to the previous estimated eight Russian air strikes on hospitals in Syria, as well as the 313 attacks on medical facilities since the start of the conflict.”

It said several of its facilities had been hit in Russia’s bombing campaign, including in the Mediterranean coastal province of Latakia and the central province of Hama on October 2 and in the northwestern province of Idlib on Tuesday.

The latest strike killed two medical personnel and at least 10 civilians, and wounded 28 civilians, it said.

Russia has strongly denied reports that its aircraft hit the hospital in the Idlib province town of Sarmin, describing them as “fake.”

The society’s president, Ahmad Tarakji, called for international action to stop hospitals and clinics being hit again.

“We call on the international community to use all means necessary to end attacks on civilians and to prevent the further targeting of healthcare facilities in Syria,” he said.

Russia began its air campaign in Syria on September 30 in order to prop up President Bashar al-Assad.

The Syrian Observatory for Human Rights reported Tuesday that of the 370 people killed in the Russian strikes since they began, only 52 are from Islamic State (ISIS), belying Russia’s claims of an anti-ISIS campaign. Of the victims 127 are civilians, including 36 children and 34 women, and the rest are largely Western backed rebel forces.

AFP contributed to this report.