TRIPOLI, Libya - Libyans hunting Moammar Gadhafi offered a $2 million bounty on the fallen dictator's head and amnesty for anyone who kills or captures him as rebels battled Wednesday to clear the last pockets of resistance from the capital Tripoli.

While some die-hard loyalists kept up the fight to defend Gadhafi, his support was crumbling by the hour. His deputy intelligence chief defected, and even his foreign minister said his 42-year rule was over.

A defiant Gadhafi vowed from hiding to fight on "until victory or martyrdom," in an audio message early Wednesday.

He may have little choice. Asked by the British broadcaster Channel 4 if a negotiated settlement or safe passage for Gadhafi from Libya was still possible, Foreign Minister Abdul Ati al-Obeidi said: "It looks like things have passed this kind of solution."

Rebel leaders were beginning to set up a new government in the capital. Their interim administration, the National Transitional Council, has been based in the eastern city of Benghazi, which fell under rebel control shortly after the outbreak of widespread protests in February.

"Members of the council are now moving one by one from Benghazi to Tripoli," said Mansour Seyf al-Nasr, the Libyan opposition's new ambassador to France.

Rebel officials are eager to prove they can bring a stable political future to Libya, and that their movement is more than an often-fractious collection of tribes, ethnicities and semiautonomous militias. Mahmoud Jibril, the head of the opposition government, outlined plans for a new constitution and elections and said officials were talking to the U.N. about sending up to 200 monitors to help ensure security in Tripoli.

But the capital was far from pacified. A day after rebels captured Gadhafi's vast Bab al-Aziziya compound, the symbolic center of his regime, loyalists were firing into the compound from an adjacent neighborhood where intense clashes broke out. Pro-regime snipers cut off the road to the airport. Four Italian journalists were kidnapped on the highway to Tripoli around the city of Zawiya, 30 miles west of the capital.

Tripoli's streets were largely empty of civilians. Rebels manned checkpoints every few hundred yards, but little could be seen beyond the debris of days of fighting and weeks of accumulated garbage.

Rebels found no sign of Gadhafi after storming his compound Tuesday, but rumors churned of his possible whereabouts. White House spokesman Josh Earnest said there was no evidence he had left Libya, but rebel officials acknowledged they could not find him.

"He might be in Sirte or any other place," Jibril said in Paris, where he met French President Nicolas Sarkozy. Sirte, a coastal city 250 miles from Tripoli, is Gadhafi's hometown and a bastion of regime support.

Khaled al-Zintani, spokesman for the rebel military council for the western mountains, said it has set up an operations room with intelligence officers, military defectors and security officers who are trying to find Gadhafi, his family, regime members and his forces. They are collecting information on the location, size and direction of any convoys.

The operations center is in the western mountains, the staging base for the rebels who marched on Tripoli.

Mohammed al-Herizi, an opposition official, said a group of Tripoli businessmen has offered a $2 million reward for the arrest or killing of Gadhafi. The rebels themselves are offering amnesty for anyone who kills him or hands him over.

"The biggest prize is to offer amnesty, not to give money," rebel spokesman Col. Ahmed Bani said.

Gadhafi vowed not to surrender. Speaking to a local television channel, apparently by phone, he called on residents of the Libyan capital and loyal tribesmen to free Tripoli from the "devils and traitors" who have overrun it.

Al-Sadeq al-Kabir, a rebel spokesman, denied media reports that Gadhafi had offered a cease-fire.

The rebels have taken control of much of Libya with the help of a relentless NATO air campaign that included about 7,500 strike attacks against Gadhafi's forces. His defenses around Tripoli melted away as the rebels rapidly advanced and entered the capital Sunday.

Jibril said a commission created with members from around Libya would write a new constitution, which would be put up for a referendum. He didn't specify a timetable but said that once a constitution is adopted, elections for parliament would be held within the next four months, and its president would be Libya's interim leader until a presidential election sometime later.

"The mission of protecting civilians is not over," Jibril said. "The other bigger and more fierce battle has not started yet. It is the rebuilding of Libya."

In the postwar period, a new army will be created, he said, and the National Transitional Council planned "to call on all those who took up arms to join either the new army or the new police force that we will constitute in coming days."