Libya's Rebels struggle to keep momentum

For weeks, opposition forces made significant progress in their fight against Libya's Muammar Qaddafi, taking control of several key towns in the east. Now, the tide may be turning.

Meanwhile, President Obama spoke by phone with British Prime Minister David Cameron. Both agree all options are on the table, including the imposition of a no-fly zone.

CBS News correspondent Mark Phillips reports that Qaddafi himself made a surprise appearance at a Tripoli hotel where foreign reporters have been staying. The embattled leader arrived in the kind of crush only he can draw, and provided no indication he's considering giving up his increasingly brutal battle to stay in power. He again said that al Qaeda was behind this rebellion.

In that battle, for the fifth-straight day, the Libyan army continued to pound the town and the people of Zawiyah, just outside the capital, which has been held for weeks by rebels. The anti-Qaddafi rebels have resisted an increasingly ferocious assault there, and stayed defiant.

For Col. Qaddafi, this pocket of resistance just 30 miles from Tripoli is an embarrassment on his doorstep, one that flies in the face of his claim that the rebellion has been brought under control. He's sent in the most notoriously ruthless unit in the Libyan army - the Khamees Brigade, headed by one of his sons - to shoot them down.

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Each time the army rolls in, the toll of dead and injured mounts. Each time the diminishing number of defenders, augmented by some army defectors, has somehow repelled the advance.

"We killed four people in the center and took their weapons, and now all the people are shouting outside because they win. Victory is near," said one defender.

Victory is uncertain and costly. Each government attack leaves wounded and dead behind. A reporter from Britain's Sky News channel has been the only outside witness to the battle. Amongst the injured are the attacking soldiers, one of them still conscious, begging for his life. The man is a tank commander pleading that he was forced to fight on the wrong side.

He may have been unlucky, but the rebels are pinned down in Zawiyah and elsewhere. Their only option is to keep fighting.

The rebel forces may not be getting any outside military help, but some international economic muscle is being brought to bear. European countries have now announced a freeze on Libyan government investments in companies there. This adds to sanctions already in force on Qaddafi family accounts.

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In the east on Tuesday, government forces unleashed a heavy barrage of rockets on a rebel contingent that tried to move out from their position at the oil port of Ras Lanouf. At least 20 wounded were rushed to the hospital in the town, some of them with legs lost and other serious injuries.

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"I was hit in the arm and leg, my friend was wounded in the stomach," Momen Mohammad, 31, said while lying in a hospital bed.

The fighting began when the rebel forces advanced west out of Ras Lanouf toward Bin Jawwad, a small town 375 miles east of the capital, fighters said.

In "company town" of Tripoli, loyalty to Qaddafi

Earlier in the day, warplanes launched at least five new airstrikes near rebel position in Ras Lanouf, one hitting a two-story house in a residential area, causing some damage. None of the strikes appeared to cause casualties, suggesting they were intended to intimidate the fighters, according to an Associated Press reporter who saw the strikes. The anti-regime forces were not taking any chances and were spreading out deep inside the desert around the area in small groups.

After a string of initial successes, the rebels have had trouble on the ground - their advance slowed by better-armed government forces counterattacking to defend Qaddafi's home turf in the west. The rebels have started realizing that enthusiasm alone won't get them to Tripoli. For days, they advanced on town after town in eastern Libya by jumping into pickup trucks and racing to the fight with no planning whatsoever. Now, even the fighters admit they need discipline, reports CBS News correspondent Mandy Clark.

Mohammed Hamza, an adviser in Libya's Foreign Ministry in Tripoli who is originally from Zawiya, said Tuesday that government forces were in control, raising the green flag of Qaddafi's rule in the square.

But a resident of the nearby town of Sabratha said people who fled from Zawiya on Tuesday afternoon told him fighting continued, with rebels back in control of the cityâ??s main square. He said the residents reported government forces controlling the entrances to the city were heavily shelling residential neighborhoods with tank and artillery fire. They said the city hospital was overwhelmed with dead and wounded and many homes had been damaged.

The various reports could not be independently confirmed. Electricity, phone and Internet services have all been cut in the city, making it impossible to reach witnesses in Zawiya.

In Benghazi, Libya's second largest city and the main rebel stronghold in east, there was an unusual attack after weeks of quiet that followed the rebel capture of the territory. Assailants in a car tossed a grenade at a hotel where foreign journalists were staying, but there were no casualties and only some light damage to windows, an opposition official said.

Representatives of the opposition said they have received an offer to negotiate the terms of Qaddafi's departure. However, they could not confirm whether the envoy who made the offer was authorized by the regime and said in any case, they would not negotiate with the government. Libyan state television denied that Qaddafi had sent an envoy to talk to the rebels.

The rebels are fighting to oust Qaddafi from power after more than 41 years, inspired by protesters who managed to topple authoritarian rulers in neighboring Tunisia and Egypt. However, the Libyan uprising has already proved much more violent.

The latest round of fighting on opposite ends of Libya's Mediterranean coast once again revealed the weakness and disorganization of both sides in the conflict.

Qaddafi's regime has been using its air power advantage more each day to check a rebel advance west toward Tripoli on the main highway leading out of the opposition-controlled eastern half of the country. The increasing use of air power underlines the vulnerability of the rebel forces as they attempt to march in open terrain along the Mediterranean coast and could prompt world powers to impose a no-fly zone over Libya to deny Qaddafi that edge.

The United States and its NATO allies edged closer Monday to formulating a military response to the escalating violence in Libya as the alliance boosted surveillance flights over the country and the Obama administration signaled it might be willing to help arm Qaddafi's opponents. Europe, meanwhile, kick-started international efforts to impose a no-fly zone.

It still appeared unlikely that U.S. warplanes or missiles soon would deploy in Libya, which has been sliding toward civil war, but the continuing violence increased pressure on Washington to do something or at least spell out its plan.

Western officials have said a no-fly zone does not require a U.N. mandate, but they would prefer to have one.