Russian jets hit Islamic State targets in the Syrian city of Palmyra and the northern province of Aleppo, Syrian state television said, quoting a military source.

The strikes destroyed 20 vehicles and 3 weapons depots in Islamic State-held Palmyra, it said. In Aleppo, they hit the towns of Al-Bab and Deir Hafer, about 20 km (10 miles) east of a military airport currently besieged by Islamic State fighters.

Al-Manar television, run by the Lebanese Hezbollah group which is allied to President Bashar al-Assad, said the Russian air force also carried out four raids in the Jabal al-Zawiya area in the northwestern province of Idlib.

Islamic State forces captured Palmyra in May, an advance which brought them closer to the core of government-held territory in western Syria. It also put the city's Roman-era ruins under the militants' control.

Syria's antiquities chief Maamoun Abdulkarim said on Sunday Islamic State fighters blew up Palmyra's Arch of Triumph, one of the most treasured monuments in the 2,000-year-old city. They had already destroyed temples and other antiquities.

Russia has carried out dozens of strikes in Syria since launching its air campaign last Wednesday.

While Moscow says its intervention targets the hardline Islamic State fighters who control much of eastern and northern Syria, many of the Russian strikes so far have hit rival insurgent forces opposed to Assad.