BENGHAZI, Libya (AP) - The scope of Moammar Gadhafi's control was whittled away Wednesday as major Libyan cities and towns closer to the capital fell to the rebellion against his rule. In the east, now all but broken away, the opposition vowed to "liberate" Tripoli, where the Libyan leader is holed up with a force of militiamen roaming the streets and tanks guarding the outskirts.
In a further sign of Gadhafi's faltering hold, two air force pilots - one from the leader's own tribe - parachuted out of their warplane and let it crash into the eastern Libyan desert rather than follow orders to bomb an opposition-held city.
International momentum was building for action to punish Gadhafi's regime for the bloody crackdown it has unleashed against the uprising that began Feb. 15.
President Barack Obama said the suffering and bloodshed in Libya "is outrageous and it is unacceptable," and he directed his administration to prepare a full range of options, including possible sanctions that could freeze the assets and ban travel to the U.S. by Libyan officials.
French President Nicolas Sarkozy raised the possibility of the European Union cutting off economic ties.
Another proposal gaining some traction was for the United Nations to declare a no-fly zone over Libya to prevent it using warplanes to hit protesters. U.N. High Commissioner for Human Rights Navi Pillay said that if reports of such strikes are confirmed, "there's an immediate need for that level of protection."
In Tripoli, Gadhafi's stronghold, protest organizers called for new rallies Thursday and Friday, raising the potential for a more bloody confrontation.
Militiamen and Gadhafi supporters - a mix of Libyans and foreign African fighters bused in - roamed the capital's main streets, called up Tuesday night by the Libyan leader in a fist-pounding speech in which he vowed to fight to the death. The gunmen fired weapons in the air, chanting "Long live Gadhafi," and waved green flags. With a steady rain, streets were largely empty, residents said.
In many neighborhoods, residents set up watch groups to keep militiamen out, barricading streets with concrete blocks, metal and rocks, and searching those trying to enter, a Tripoli activist said.
Gadhafi's residence at Tripoli's Aziziya Gates was guarded by loyalists along with a line of armed militiamen in vehicles, some masked, he said. The radio station building downtown was also heavily fortified. In one western neighborhood, security forces stormed several homes and arrested three or four people, a witness said, while tanks were deployed on the eastern outskirts, witnesses in at least one neighborhood said.
But below the surface, protesters were organizing, said the activist. At night, they fan out and spray-paint anti-Gadhafi graffiti or set fires near police stations, chanting, "The people want the ouster of the regime," before running at the approach of militiamen, he said.
In opposition-controlled Benghazi, the eastern city where the uprising began, residents held a mass rally outside the city's main courthouse, vowing to support protests in the capital, said Farag al-Warfali, a banker. They also called a one-day fast in solidarity with them. Afterward, young men went into the courthouse to register to obtain weapons, which had been looted from police stations and military bases and then turned over to the city's new rulers, he said.
The idea is to "take their weapons and march toward Tripoli," al-Warfali said, although Benghazi lies 580 miles east of the capital, and territory still loyal to Gadhafi lies between them.
There were similar calls in Misrata - several hours' drive from Tripoli, the closest major city to the capital to fall to anti-government forces. A mosque called residents to come to "jihad," or holy war, in support of the anti-Gadhafi camp, said one resident, Iman.
"We are going to join forces with our brothers in Tripoli," she said.
The extent of Gadhafi's control over the country he has ruled for 41 years had been reduced to the western coastal region around Tripoli, the deserts to the south and parts of the center.