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 Moammar Gadhafi's nearly 42-year regime, but scattered battles erupted and the mercurial leader's whereabouts remained unknown.
The international community called on Gadhafi to step down and moved ahead with post-war planning as euphoric residents celebrated in the Green Square, the symbolic heart of the Gadhafi regime, but colleagues warned he wouldn't go easily.
NATO promised to continue airstrikes until all pro-Gadhafi forces surrender or return to barracks.
The relative ease with which the rebels captured Tripoli in an hours-long blitz backed by NATO airstrikes showcased the evolution of the opposition fighters who first rose against the regime six months ago, swiftly capturing the eastern part of the vast North African nation but failing to muster enough punch to advance westward toward Tripoli even with the help of months of NATO airstrikes.
For months, the rebels were judged to be big on zeal but short on organization and discipline, but their stunning success in Tripoli showed a high level of planning, coordination and discipline.
In London, British Prime Minister David Cameron said frozen Libyan assets would soon be released to help the country's rebels establish order, saying Gadhafi's regime was "falling apart and in full retreat."
Rebel spokesman Mohammed Abdel-Rahman, who was in Tripoli, cautioned that pockets of resistance remained and that as long as Gadhafi remains on the run the "danger is still there."
Clashes broke out early Monday at Gadhafi's longtime command center known as Bab al-Aziziya early Monday when government tanks emerged from the complex and opened fire at rebels trying to get in, according to Abdel-Rahman and a neighbor. An AP reporter at the nearby Rixos Hotel where foreign journalists stay could hear gunfire and loud explosions from the direction of the complex.
Tripoli resident Moammar al-Warfali, whose family home is next to the compound, said there appeared to be only a few tanks belonging to the remaining Gadhafi forces that have not fled or surrendered.
"When I climb the stairs and look at it from the roof, I see nothing at Bab al-Aziziya," he said. "NATO has demolished it all and nothing remains."
The Rixos also remained under the control of Gadhafi forces, with two trucks loaded with anti-aircraft machine guns and pro-regime fighters and snipers posted behind trees. Rebels and Tripoli residents set up checkpoints elsewhere in the city.
The rebels' top diplomat in London, Mahmud Nacua, said clashes were continuing in Tripoli, but opposition forces controlled 95 percent of the city. He vowed Gadhafi would be found, saying "the fighters will turn over every stone to find him" and make sure he faced justice.
A rebel field commander said reinforcements were arriving at Tripoli by sea from the north as well as the south and the southeast.
"Our fighters are coming from all directions and, God willing, today we will liberate the whole city," the commander, Suleiman Sifaw, told The Associated Press.
State TV broadcast bitter audio pleas by Gadhafi for Libyans to defend his regime as the rebels advanced on Sunday. 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.