AMMAN (Reuters) - Russian and Syrian warplanes struck Islamic State outposts around Palmyra on Monday in an attempt to expel them a day after they had retaken the ancient city, but the ultra-hardline group said it had continued advances to the west.
Sunday's loss of Palmyra, despite dozens of Russian airstrikes intended to hold militant fighters back, was a major reversal for Syria's government and its Russian backer. They had seized the settlement with its Roman-era city and spectacular ruins only in March and had staged a widely publicised concert there.
The Syrian army said both its warplanes and Russian jets hit militant posts on the outskirts of Palmyra on Monday, killing dozens and destroying some military equipment.
The UK-based Syrian Observatory for Human Rights said dozens of Syrian soldiers and allied militias were killed during the fighting that led to the collapse of the army's defences in the heavily garrisoned city.
A statement by Islamic State said its fighters had advanced west of Palmyra towards the T4 airbase, one of the largest military airbases the country, where the Russian airforce has a large presence and shelled it.
"The airport is being targeted with all types of weapons and missiles," the statement said. Reuters could not verify the claim
"After capturing Tadmur (Palmyra) the Khilafah soldiers continued their progress today after ferocious clashes with the army and its militias," the statement by Islamic State's Homs Wilayat (province) said.
Russia said on Sunday Islamic State had deployed over 4,000 fighters in the assault drawing on significant forces from their strongholds in Raqqa and Deir Zor.
Moscow said Washington's decision to suspend active operations in Syria's Raqqa had allowed the militants to redeploy to Palmyra. [R4N1E0025]
The Observatory confirmed the militants had succeeded in a five-day offensive to gain control of several gas and oil installations including the Jazal, Jahar and Mahr oil and gas fields and the Hayan Gas Company, north west of the city that feed electricity to large areas of eastern Syria.
They also seized a string of villages and strategic heights around Palmyra, a small military airport and grain silos east of the city.
Editing by Ralph Boulton