Syrian regime forces backed by Russian air strikes advanced in the centre of the country on Monday, sparking the fiercest clashes with rebels since Moscow began its air campaign, a monitor said.
The Syrian Observatory for Human Rights said regime forces had entered the village of Kafr Nabuda in Hama province as they press an operation on both sides of the highway between the capital Damascus and second city Aleppo.
"Regime forces captured the southern district of Kafr Nabuda backed by more than 20 Russian air strikes," said Observatory director Rami Abdel Rahman.
"The clashes are the fiercest since the Russian air campaign began on September 30."
Syrian government forces appear to be targeting the town of Khan Sheikhun, which lies on the strategic highway, just across the provincial border in neighbouring Idlib.
Many of Russia's air strikes so far have been focused on the area where the borders of Hama, Idlib and Latakia provinces meet.
Latakia province on the Mediterranean coast is a stronghold of the regime and the location of President Bashar al-Assad's ancestral village.
Idlib province is controlled by a powerful rebel alliance called the Army of Conquest which includes Al-Qaeda affiliate Al-Nusra Front.
In recent months, the alliance has sought to expand from Idlib into Hama and the strategic Sahl al-Ghab plain between the three provinces in a bid to target Latakia.
Abdel Rahman said the rebels were sending reinforcements to Kafr Nabuda to battle the regime, which was also shelling other parts of Hama and Latakia provinces.
Russian began air strikes in Syria on September 30, saying it was targeting the Islamic State group and other "terrorists."
But rebels and their backers accuse Moscow of targeting mainly non-jihadist groups.
