Intense fighting raged throughout Damascus for a second day and much of Syria continued to be cut off from the outside world as an emboldened opposition attempted to break through defences in the capital.
Internet access remained off limits to almost all of the country and Damascus airport was again closed as battles were fought nearby between the Syrian army and rebels. Mortar rounds fired by opposition groups damaged at least one runway and international airlines suspended flights.
Regime reinforcements, including some of its most loyal and capable units, were understood to be trying to push rebels back to rural areas and consolidate their hold on parts of Damascus where the key institutions of state are located.
After months of skirmishes with the army on the capital’s outskirts, rebel groups said they were attempting to storm strongholds of President Bashar al-Assad’s regime, including security buildings from where the regime side of the civil war has been run and the presidential palace.
Seizing the airport was also a stated goal of the second co-ordinated attempt to take Damascus in the past four months.
The first ended in failure, followed by a series of crushing regime reprisals on opposition communities. The new push appears to have been sparked by a series of advances elsewhere in the country, especially in the north and east, where militant groups near the Iraqi border have made sweeping gains.
“We want to liberate the airport because of reports we see and our own information we have that shows civilian aeroplanes are being flown in here with weapons for the regime,” rebel spokesman Musaab Abu Qitada said of the latest assault. “It is our right to stop this.”
Two Austrian members of a UN peacekeeping force were shot in crossfire near the airport on Thursday and evacuated to Israel through the Golan Heights. They are now in hospital in the northern city of Haifa.
In far eastern Syria, the jihadist group Jabhat al-Nusra was believed to have seized several oilfields including the Omar field, north of the town of Mayedin.
Al-Nusra, which contains scores of militants battle hardened in Iraq, was instrumental in overrunning the Mayedin military base last week. It is believed to have used the booty of weapons seized during the raid to storm key regime outposts and assets ever since.
The rebel momentum is largely being fuelled by weapons seized during recent raids. Syrian forces are thought to have lost control of much of the east of the country and to be maintaining only a tenuous hold on the city of Deir Azzour.
In the north fighting again flared in and around Aleppo, where jihadists have combined with Free Syria Army units both in the opposition-held countryside and in the city itself.
Rebels fighting near Aleppo have shown an increasing strategic awareness since they stormed Syria’s second city from the hinterland towns and villages in mid-July.
After several months of stalemate, opposition forces have been picking off regime bases and outposts that were still operating in the north. They have also succeeded in cutting several key roads that had been used by loyalist troops as supply lines in the western half of Aleppo, which is still under regime control.
The fighting in the ancient city has seen no side yield substantial ground. It is still split roughly in half north to south.
After many months of pleading for international help to defeat the Assad regime, rebel groups contacted by the Guardian say they are beginning to feel confident in their ability to finish by themselves what they started, as civilian protests gradually changed into full-blown insurrection over the past 20 months.
While Damascus does not appear to be at imminent risk of falling, Assad’s battle-weary forces remain stretched and heavily engaged in all corners of the country. Recent defectors speak of low morale and growing problems with supply lines in the city.
The outgoing US secretary of state, Hilary Clinton, who with Barack Obama had refused to supply weapons to the Free Syria Army, said recent developments showed the dynamic in Syria was changing.
“I don’t know if you can say that the entire country is at a tipping point, but it certainly seems that the regime will be harder pressed in the coming months,” she said. “It appears as though the opposition is now capable of holding ground and that they are better equipped and more able to bring the fight to the government forces.”