Syrian war planes carried out a series of air raids Tuesday on positions held by the Islamic State jihadist group in eastern Deir Ezzor province, an NGO and state media said.
"Syrian army forces targeted headquarters and warehouses storing weapons and ammunition belonging to the terrorist group known as the Islamic State... destroying them completely," Syria's state news agency SANA reported.
The agency added that the army had also targeted groups of IS members, "killing large numbers of them."
The Syrian Observatory for Human Rights, a Britain-based monitoring group, said the Syrian army had carried out at least 12 strikes across the oil-rich province.
"It's the first time since the Islamic State took control of most of Deir Ezzor that warplanes have carried out such intensive and pinpoint raids against Islamic State positions in the region," Observatory director Rami Abdul Rahman said.
At least seven civilians were killed in the raids, along with an unspecified number of jihadists, the monitoring group added.
Among the targets of the raids was a training camp in the west of the province, Abdul Rahman added.
The raids come a day after Syria said it was willing to cooperate with the international community to counter the threat posed by IS, which declared a "caliphate" in territory it holds in Syria and Iraq.
The jihadist group has raised international concern after lightning advances in Iraq and a slew of abuses including the murder of US journalist James Foley, who was kidnapped in Syria.
The United States is already carrying out air strikes against the group in Iraq and US officials have said they are ready to send spy planes into Syria to track IS jihadists.
Elsewhere in Syria, the Observatory said at least 33 people died in fighting between the army and Al-Nusra Front -- Al-Qaeda's Syrian affiliate -- in Zabadani northeast of the capital Damascus.
Al-Nusra has seized five army checkpoints in the region during three days of clashes that left 20 soldiers dead, along with 13 Nusra fighters, the Observatory said.
Zabadani is considered strategic because of its proximity to the Lebanese border and the mountainous border region where many rebels sought refuge after being routed from the Qalamun area earlier this year.