Forces loyal to Colonel Muammar Gaddafi have encircled rebels in the town of Zawiyah after a day of pitched battles in the far west and east of Libya that intensified the pressure on the embattled dictator.
The fighting in Zawiyah, 30 miles west of the capital, Tripoli, was some of the most savage so far of the two-week uprising that has seen the east of the country fall into rebel hands and the veteran autocrat's rule pushed to the brink of collapse.
A contact of the Observer inside the city said the fighting was intense. "You must tell the world what is happening," the man said by phone. "Snipers are firing at anyone who moves."
Another inhabitant reported that at least 20 tanks had rolled into the town and had started shelling its square. "The fighting has intensified and the tanks are shelling everything on their way," Abu Akeel said. "They have shelled houses. Now they are shelling a mosque where hundreds of people are hiding. We can't rescue anyone because the shelling is so heavy."
A doctor in Zawiyah said that at least 30 people, mostly civilians, had been killed during fighting yesterday, bringing to 60 the death toll from two days of battles for control of the coastal town.
In the rebel stronghold of Benghazi, an SAS unit of up to eight men was being held after a secret mission to put British diplomats in touch with leading opponents of the regime ended in humiliation, the Sunday Times reported. The soldiers were captured as they escorted a junior diplomat through rebel-held territory in the east, according to the newspaper.
The onslaught came as the oil town of Ras Lanuf, around 250 miles west of the rebel stronghold of Benghazi, fell to anti-government forces after a day of fighting that left at least 20 dead. Residents of Ras Lanuf reported running battles between loyalist forces and rebels for 24 hours, before the government troops withdrew in what some observers have suggested was more of a tactical retreat than surrender. The area between the two towns is now being treated as a front line in a protracted campaign that many in Benghazi fear is beginning to turn into a civil war.
Some officials in Benghazi's nascent organising committee hailed the fall of the strategically important town as an important landmark in an eventual push towards Tripoli. However rebel commanders urged caution, insisting they must consolidate their gains before trying to advance. They point out that Sirte, further up the highway and in the hands of Gaddafi's troops, remains impassable.
After a fortnight of clashes, there are signs the battle for control of Libya is approaching a stalemate.
In an apparent softening of earlier declarations, leaders of the revolt said talk of a push on Tripoli was premature. Some went as far as to suggest that unless international moves are made to keep Gaddafi's air force out of the skies, the push would not take place.
Gaddafi has so far made only limited use of his 250 fighter jets in an apparent bid to reduce the risk of international intervention in the conflict. Establishing a no-fly zone would shift the balance of power and allow rebels to advance.
The Observer saw bombing runs near rebel positions on the outskirts of Brega last week. Witnesses said that jets also bombed targets in Ras Lanuf on Saturday and an attack helicopter fired on rebel-held areas.
However, most of the bombs appear to have fallen short – a result that some rebel leaders say is deliberate. "He is playing with us," said Major Ibrahim Fatouri in Benghazi. "This is the one time in recent years that he has cared what the world thinks of him. When you are tired of watching, the pilots will start hitting targets."
An intensification of the fighting came as the shadow foreign secretary, Douglas Alexander, criticised Europe's response to the crisis.
In an article for the Observer's website, Alexander said: "The EU has been slow off the mark on Libya. The UK government should now propose that Friday's EU council become a joint emergency summit held with the Arab League."
Heightened concerns that unrest will spread across the Middle East have prompted the government to issue new advice to travellers. The Foreign Office said: "We recommend that all British citizens without a pressing need to remain in Yemen should leave by the commercial flights currently available."
Meanwhile, Saudi Arabia, which has become concerned that the uprisings might spawn copycat protests, banned all marches. The announcement signalled that the recent small-scale protests by the Shia minority in the oil-producing east of the country would no longer be tolerated.
Thousands of Shia protesters in Bahrain formed a human chain around the capital, Manama, as their campaign to loosen the Sunni monarchy's grip on power entered its third week.