Syrian war plane crashes near Islamic State-held city - resident
It was not immediately clear what brought down the plane, which the Syrian Observatory for Human Rights said had crashed on the outskirts of Raqqa, some 400 km (250 miles) northeast of Damascus.
The Syrian air force has been bombing Islamic State-controlled territory on a near daily basis since the group seized the Iraqi city of Mosul in June and declared a cross-border caliphate in Iraq and Syria.
Syria has offered to join a coalition the United States is assembling to fight Islamic State, but Western governments see President Bashar al-Assad as part of the problem and have ruled out the idea of such cooperation.
U.S. President Barack Obama said last week he would not hesitate to hit Islamic State in Syria.
Islamic State controls roughly a third of Syria, including most of Deir al-Zor province, which borders Iraq.
The Observatory, which gathers information from a network of activists on the ground, reported five air raids on Raqqa on Tuesday.
(Writing by Tom Perry; Editing by Hugh Lawson)