Men stand along a crater caused by what activists said was a Russian air strike in Latamneh city on Wednesday, in the northern countryside of Hama, Syria.

At least 12 jihadists from the Islamic State of Iraq and Syria (ISIS) group have been killed in Russia’s first air strikes on the extremist faction’s main Syrian bastion, a monitoring group said.

Russia’s defense ministry confirmed it had carried out strikes on Raqqa province on Thursday.

It said Russian Su-34 planes struck “an ISIS training camp near the village of Maadan Jadid,” 70 km (45 miles) east of Raqqa city, and “a camouflaged command post at Kasrat Faraj, southwest of Raqqa.”

The Syrian Observatory for Human Rights said the strikes had killed at least a dozen IS fighters.

“Last night, Russian strikes on the western edges of Raqqa city, and near the Tabqa military airport, killed 12 ISIS jihadists,” Observatory head Rami Abdel Rahman said on Friday.

He said their bodies were transported to a hospital in the province.

Moscow’s defence ministry said Friday that its war planes had “conducted 18 sorties on 12 positions held by the Islamic State terrorist group in Syria” since Thursday.

The statement said Russian raids destroyed “a command post and communications center” held by ISIS in Daret Ezza in northern Aleppo province, as well as bunkers and weapons depots in Maaret al-Numan and Habeet in northwest Idlib province.

Raids also struck “an ISIS command post” in Kafr Zeita in central Hama province.

According to the Observatory, none of these areas are controlled by ISIS, though most are held by Al-Qaeda’s Syrian affiliate Al-Nusra Front.

And according to a Syrian military source, Russian strikes on Friday also targeted an ancient Christian town in Homs province seized by ISIS on August 5.

“Russian warplanes struck Al-Qaryatain this morning,” the source said.