A strategic town is lost in the east with another expected to follow soon. In the west, a symbolic centre of resistance is about to suffer an onslaught that it is unlikely to survive. With no international action to stop Muammar Gaddafi's fierce offensive, the survival of Libya's revolution hangs in a precarious balance.
Just four days ago the picture was very different: the rebel fighters were seemingly on a march to the capital, Tripoli, and the enemy was in disarray and retreat. But a series of misjudgements, and chronic lack of planning and organisation, have resulted in a dramatic reversal. The regime's troops are poised to strike at Benghazi, the capital of "Free Libya''.
By yesterday afternoon, the opposition had abandoned Ras Lanuf, an oil port on the key coastal route. They withdrew to Aghala, outside Brega, another petrochemical complex. Control of the two locations would provide the regime with the reserves of fuel needed for the tanks and armoured cars arriving in increasing numbers on the frontline. It would also put Tripoli in a position to shut down power supplies to Benghazi.
Taking Brega would also give the government an airport, allowing the Gaddafi military to bring in reinforcements. Some of these are available after the recapture of Zawiya, and others may follow if the same fate befalls Mistrata, the other main focal point of protest near Tripoli.
The Libyan navy was used for the first time in recapturing Ras Lanuf: salvoes coming in from the sea caught the revolutionary cadres unawares, and provided fresh evidence of the regime's forces preparing themselves for the battles ahead. But it was an air strike by the enemy that, rebel commanders hope, will slow down any thrust towards Benghazi.
On Friday afternoon, two missiles landed in the petrochemical complex outside Ras Lanuf amid concrete barrels of crude oil, starting a blaze. Ethlene is also produced at the plant and, if it gets overheated and ignites, the devastation could spread for 40 kilometres; a situation that some believe would hold forces up for about five days. "No operation can take place if that happens," said Colonel Bashir Abdul-Gaddar, in charge of rebel forces in Aghala. "They bombed the place. It was a criminal thing to do."
Judging by the speed of the retreat and thinning of rebel ranks, many already believe the situation is highly dangerous. By late yesterday afternoon, their positions were being pounded by mortars, heavy machine-guns and the weapon the rebel fighters fear most: Russian-made Grad rockets, relatively ancient in terms of modern warfare, but taking a steady toll of lives in this low-tech conflict.
In Benghazi, the provisional government, known as the national council, insisted the setback was purely temporary. General Abdel Fattah-Younis, a former regime interior minister (whom William Hague consulted before sending the mission that ended with British Special Forces soldiers being arrested), was adamant there would be a counter-attack: "Yes, the Gaddafi men control Ras Lanuf and the oil terminal. But this is only temporary, we shall recover them in the next few days."
Col Abdul-Gaddar has been told he will get more resources. "I was told that 50 tanks would be coming. I can do with some more men and guns now. We shall certainly try to defend Brega and – inshallah – we shall throw them back. Losing it will mean big problems and we cannot let that happen."
The togetherness the rebels enjoyed two weeks ago has become increasingly frayed in recent days in the face of reverses. The Shabaab, volunteers who have joined the revolutionary forces, are critical of what they perceive as the reluctance to take part in missions of the Libyan military who have defected to the rebels. Mehdi Mohammed, while waiting to evacuate from Ras Lanuf, complained about senior officers refusing pleas to go into Bin Jawad, the next town in regime hands, to secure the release of captured comrades.
The state television channel had shown images of the prisoners, looking terrified, lying face down on the ground with their arms tied behind their backs. A Libyan army officer was standing in front of them saying into a microphone: "We killed you in Bin Jawad. We shall kill you in Ras Lanuf. We shall kill you wherever we find you in Libya."
"We said we could not leave them there, to be tortured, to be killed," Mr Mohammed said. "There are also injured people there we could get out. But the soldiers would not go: they are not serious, they do not have the heart for this. Now we are going backwards to Brega. But why are we doing this? We should be going forward to attack Bin Jawad. Instead we are giving up Ras Lanuf."
The professional troops counter that the Shabaab are unwilling to be organised and take orders. Captain Selim Idris, who has left his army artillery regiment, said: "They are enthusiastic but they are untrained. They want to charge off and fight, but we need to have co-ordination as well. It is also difficult to get some of them to hold positions. That is what happened in Bin Jawad."
When I arrived at Bin Jawad last weekend there was no one in control. The regime forces had fled, a group of local men waited patiently at the gate to welcome the revolutionaries. A Shabaab group headed towards the town to "consolidate" there before moving on to Sirte, Col Gaddafi's birthplace and a loyalist stronghold.
However, after celebrating victory with the local people, the rebels decided to withdraw to Ras Lanuf. "They did not like the food and they did not like where they would have had to sleep, so they went back," said Captain Idris. The next day the fighters returned to Bin Jawad, straight into an ambush, losing more than 60 men. The regime forces subsequently used the town to launch the assault now rolling towards Brega.
There had been a regime attack on Brega two weeks ago. On that occasion it was driven off following a day of fighting in which it failed to capture the airport and the oil plant. Dr Mohammed Yunis treated the injured there. He has subsequently seen casualties from the front steadily increase. "We send all the more seriously injured to Benghazi. We do not have the facility to deal with too many cases like that here. If the town is attacked again, we shall have a major problem," he said. "The severity of the injuries has been rising. A lot of people have been hit by heavy-calibre weapons. There have been a lot of amputations. There is the possibility of a lot of civilian casualties if there is an attack, although many people are already leaving Brega."
Around a dozen people were taken away by the Gaddafi troops during their last incursion into the town. Among them was 39-year-old Mohammed Nistri who worked at the oil plant. "We do not know what has happened to him, where he is imprisoned," said his brother, Samir. "He was not involved in politics so there is no reason for this to be happening. But we cannot afford to take any risks: we can see the fighting is getting closer and I am going to move our family out of here for a few days. We need to move a long way, maybe to Tobruk. We have family living there."
In Benghazi, Mustapha Abdul Jalil, a former justice minister, now a member of the national council, repeated the call for the West to impose a no-fly zone, warning: "If his [Gaddafi's] planes and ships are nor checked, there will be a catastrophe in Libya."
The Arab League, meeting in Cairo, has backed the proposal, but also stated that it was unclear who would actually enforce it. Col Gaddafi has warned that Libya will be "turned into another Vietnam if there is foreign interference".
Mr Jalil, who had at one stage declared himself the head of the provisional government before having to retract the claim, dismissed any possibility of a negotiated settlement in an effort to avoid further bloodshed.
"No, all the people around the country want Gaddafi to leave and there is no way we can negotiate another option," he said. "The people don't want him to rule any more. They are between two choices: either to be killed or to fight to the end."
One of those given this choice by Mr Jalil was Karim Ibrahimi, 19, a student and member of Shaabab. How was he feeling as another enemy artillery barrage landed? "I wanted to fight for the revolution and so I am here. We want Gaddafi to go. But it is easy for a lot of people back in Benghazi to say a lot of things. They should come here and see what it's like."
Diplomacy: Arab League calls on UN to impose no-fly zone
In a decision that leaves Muammar Gaddafi more isolated than ever, in a unanimous vote the Arab League called on the UN yesterday [sat] to support a no-fly zone over Libya. Foreign ministers from the 22-member bloc, meeting in Cairo, said that Gadaffi's government had "lost its sovereignty".
The backing of the regional body confers legitimacy on the plan, whose prime movers are Britain and, to a lesser extent, the US. Many western countries had shied away from supporting a no-fly zone without Arab support.
The League gave a clear signal of support to the rebels' interim government, the National Libyan Council, saying they would establish contacts with the group and calling on other states to provide it with "urgent help". A statement from the League added that the rebels had suffered "grievous violations and serious crimes by the Libyan authorities, which have lost their sovereignty."
The Secretary-General of the League, Amr Moussa made it clear that its support for a no-fly zone was conditional on its use to protect Libyan civilians and foreigners in the country and not as a military intervention. The statement from the League also says that it rejects "all kinds of foreign intervention" in Libya, but warns that "not taking the necessary action to end the crisis will lead to intervention in Libya's foreign affairs."
That stance may have been intended to win support from the government of Syria, which, with Lebanon, Algeria, Sudan and Morocco has been an outspoken opponent of foreign intervention in events in the Arab world.
It remains to be seen whether the decision by the League will have any impact on the Obama administration, which, compared to David Cameron's enthusiasm, has been lukewarm in its support for a no-fly zone.