TRIPOLI, Libya – Several hundred tribal elders gathered Thursday in the Libyan capital in what a government official said was a show of widespread support for Moammar Gadhafi. Rebels dismissed the claim as bogus.

In Rome, U.S. Secretary of State Hillary Rodham Clinton said the best way to protect Libya’s people is to get Gadhafi to relinquish power. “This is the outcome we are seeking,” she told representatives from 22 nations and organizations.

Gadhafi has tried to crush an 11-week-old rebellion against his rule with tactics that have included shelling rebel-held towns, particularly in the western part of the country that largely remains under his control. Rebels hold most of eastern Libya.

On Thursday, Libyan troops fired Grad rockets toward the outskirts of the rebel-held town of Nalut in a remote western mountain area. A day earlier, Gadhafi loyalists shelled the port area of the city of Misrata, the biggest rebel stronghold in the west. The shelling killed four people, including two children, from a migrant workers’ camp as an aid ship was docked there.

Asked about Wednesday’s shelling, Libyan government spokesman Moussa Ibrahim said the port area is within the range of fire of the Libyan forces and that “we won’t allow any ship of any kind to come in unless it has our permission.”

Last week, Libyan forces were caught by NATO laying anti-shipping mines off Misrata. NATO vessels have been searching for mines since then. Two were detonated shortly after the mine-laying was detected.

Britain said Thursday that its naval forces knocked out a mine left about a mile from Misrata’s harbor. The port is the only lifeline for the city of 300,000, which has been besieged by Gadhafi’s forces for more than two months.

In Tripoli, meanwhile, foreign reporters were taken by government minders to a large tent where hundreds of tribal elders had gathered. Reporters were told that about 2,000 chiefs were present, that they represent 850 Libyan tribes, and that the gathering was organized by the tribes, not the regime. The government also released a list of what it said were the names of the tribes.

“It’s another proof that the Libyan people are rallying behind the leadership,” Ibrahim said of the gathering. Several speakers at the conference called for national unity, urged rebels to disarm and demanded that the international community halt its bombing campaign, which began in mid-March with the aim of protecting Libyan civilians against Gadhafi’s troops.

A rebel spokesman dismissed claims that those attending the Tripoli conference represented all Libyan tribes.

“Libya doesn’t have 850 tribes,” said Fathi Baja, head of the political committee of the rebels’ Transitional National Council, in the eastern city of Benghazi. “Gadhafi is just a big liar. … He never had any legitimacy. The Libyan people did not choose him.”