TRIPOLI, Libya - Libyan rebels claimed to be in control of most of the Libyan capital on Monday after their lightning advance on Tripoli heralded the fall of Muammar Qaddafi's nearly 42-year regime, but scattered battles erupted and the mercurial leader's whereabouts remained unknown.
Qaddafi's defenders quickly melted away as his 42-year rule crumbled, but reports of an elite unit of loyalist forces heading for the capital served as evidence that the final battle was not yet won.
Heavy clashes broke out near Qaddafi's compound in Tripoli on Monday.
Rebel spokesman Mohammed Abdel-Rahman said tanks emerged from the complex, known as Bab al-Aziziya, early Monday and began firing.
An Associated Press reporter at the nearby Rixos Hotel, where many foreign journalists are staying, could hear gunfire and loud explosions for more than 30 minutes.
A rebel spokesman who identified himself only as Nasser told Al Jazeera television that Qaddafi's troops remained in control of four sections of Tripoli, "only about 15 to 20 percent of the city," he said, according to Reuters news agency.According to Reuters, reports on Arabic television networks said the elite Khamis brigade, commanded by Qaddafi's son of the same name, was heading into central Tripoli to confront the rebels. There were earlier reports of a column of rebel fighters hundreds-strong moving into Green Square. Both sides reportedly had tanks and other medium and heavy artillery. Reuters reported that, according to a rebel commander, the fighters had approached Qaddafi's compound in the capital and were meeting resistance from the dictator's forces there. The commander told Reuters a "big number" of rebels had been killed in fighting inside Tripoli on Monday.
Abdel-Rahman said Qaddafi's troops remain a threat to the rebels' advance, and that as long as the autocrat remains on the run, the "danger is still there."CBS News correspondent Barry Petersen reports that it was remarkable how united and how well-organized the rebels seemed to be on Monday, likely thanks to training and material support from NATO.
NATO said it would continue enforcing the no-fly zone over Libya until all pro-Qaddafi forces surrendered. The European Union said sanctions imposed on Qaddafi's regime would remain in place, but stressed the ability to "lift them fairly rapidly," should conditions allow.Britain's Prime Minister David Cameron emerged from Number 10 Downing Street in London to say millions in frozen Libyan assets could soon be released to help whatever government emerges maintain control.
State TV broadcast Qaddafi's. Opposition fighters captured his son and one-time heir apparent, Seif al-Islam, who along with his father faces charges of crimes against humanity at the International Criminal Court in the Netherlands. Another son was under house arrest.
"It's over, frizz-head," chanted hundreds of jubilant men and women massed in Green Square late Sunday, using a mocking nickname of the curly-haired Qaddafi. The revelers fired shots in the air, clapped and waved the rebels' tricolor flag. Some set fire to the green flag of Qaddafi's regime and shot holes in a poster with the leader's image.
Green Square - until this weekend the epicenter of pro-Qaddfi demonstrations in the capital - was renamed "Martyrs' Square" by many celebrating there over night.
The startling rebel breakthrough, after a long deadlock in Libya's 6-month-old civil war, was the culmination of a closely coordinated plan by rebels, NATO and anti-Qaddafi residents inside Tripoli, rebel leaders said. Rebel fighters from the west swept over 20 miles in a matter of hours Sunday, taking town after town and overwhelming a major military base as residents poured out to cheer them. At the same time, Tripoli residents secretly armed by rebels rose up.
Al-Baja, the head of the rebels' political committee, said the opposition's National Transitional Council (NTC) had been working on the offensive for the past three months, coordinating with NATO and rebels within Tripoli. Sleeper cells were set up in the capital, armed by rebel smugglers. On Thursday and Friday, NATO intensified strikes inside the capital, and on Saturday, the sleeper cells began to rise up.When the battle for Tripoli is eventually won, the NTC will face a host of challenges as it works to reverse four decades of inter-tribal feuding encouraged by Qaddafi for political reasons, to try and unite a divided nation, former Undersecretary of State Nicholas Burns tells "The Early Show". Burns, who is now a professor of diplomacy and international politics at Harvard, tells CBS News that Qaddafi himself, if not apprehended quickly by rebel forces, could try and lead a domestic insurgency against any new government. "It may be a Saddam situation," said Burns, referring to the deposed Iraqi leader who disappeared after U.S. forces swept Baghdad and was later discovered hiding in a small underground bunker.
President Obama said Libya was "slipping from the grasp of a tyrant" and urged Qaddafi to relinquish power to prevent more bloodshed.
"The future of Libya is now in the hands of the Libyan people," Obama said in a statement from Martha's Vineyard, where he's vacationing. He promised to work closely with rebels.
By the early hours of Monday, opposition fighters controlled most of the capital. The seizure of Green Square held profound symbolic value the plaza was the scene of pro-Qaddafi rallies organized by the regime almost every night, and Qaddafi delivered speeches to his loyalists from the historic Red Fort that overlooks the square. Rebels and Tripoli residents set up checkpoints around the city, though pockets of pro-Qaddafi fighters remained. In one area, AP reporters with the rebels were stopped and told to take a different route because of regime snipers nearby.
Abdel-Hakim Shugafa, a 26-year-old rebel fighter, said he was stunned by how easy it was. He saw only about 20 minutes of gun battles as he and his fellow fighters pushed into the capital at nightfall.
"I expect Libya to be better," said Shugafa, part of a team guarding the National Bank near Green Square. "He (Qaddafi) oppressed everything in the country health and education. Now we can build a better Libya."
In a series of angry and defiant audio messages broadcast on state television, Qaddafi called on his supporters to march in the streets of the capital and "purify it" of "the rats." He was not shown in the messages.
His defiance raised the possibility of a last-ditch fight over the capital, home to 2 million people. Government spokesman Moussa Ibrahim claimed the regime has "thousands and thousands of fighters" and vowed: "We will fight. We have whole cities on our sides. They are coming en masse to protect Tripoli to join the fight."
But it seemed that significant parts of Qaddafi's regime and military were abandoning him. His prime minister, Al-Baghdadi Al-Mahmoudi, fled to a hotel in the Tunisian city of Djerba, said Guma el-Gamaty, a London-based rebel spokesman.