Bani Walid - Gadhafi Tribes Clash In Two Libyan Locales - Anti

NEW:An anti-Gadhafi official say a Sirte offensive will be in days, giving people time to flee

Arab, Berber tribesmen that joined to oust Gadhafi clash in two Libyan locales

A Gadhafi spokesman vows to keep fighting, claims success in Bani Walid

The battle rages on in beseiged Sirte, with urgency growing to get in humanitarian aid

Tripoli, Libya (CNN) Members of two Libyan tribes who fought together to unseat Moammar Gadhafi and his loyalists clashed Saturday, infighting among opposition forces that comes as a key ally of the longtime leader vowed to keep up the fight.

Ahmed Hussein, a resident of Badr, told CNN that Berber tribesmen from Nalut used Kalashnikov rifles and machine guns in an attack on Seaan Arab forces in that mountainous western Libyan city. A family of three caught in the crossfire was killed, he claimed.

"Nalut rebels were welcome to our town during the revolution, but now they barge in with their weapons searching the houses and scaring the residents," said Hussein, who witnessed the attacks.

Seaan Arab fighters, meanwhile, attacked Berbers from Nalut while they were posted in the Kremia neighborhood of Tripoli.

Louie Zintan, a Libyan resident who witnessed this clash and has worked for CNN, said he heard the two sets of anti-Gadhafi forces negotiating a truce and talking of exchanging prisoners. A Tripoli-based anti-Gadhafi fighter serving as a mediator warned that they might ignite a tribal war, should the fighting continue.

A National Transitional Council spokesman confirmed the confrontations, saying it was the second time the Amazigh another term for the Berber group that comprises about 10% of Libya's population, according to Amazigh student and opposition fighter Ahmed Hatem had clashed with the Seaan Arab forces.

It is the first time, however, that a firefight has occurred outside mountain areas and instead in Tripoli, said NTC spokesman Abdul Rahmad Busin.

"It is just an isolated incident, due to old feuds spilling into the streets," Busin said, adding he was hoping for a positive resolution to such issues. "The (opposition) security council is working really hard to unite all the brigades."

Just over a month ago, many members of tribes around Libya celebrated as anti-Gadhafi forces captured the capital of Tripoli, after having taken most other major cities in the North African nation. Yet the battle against Gadhafi loyalists isn't over, a loyalist spokesman insisted Saturday.

"We are not scared of fighting," Musa Ibrahim, who had been a major public face representing Gadhafi, said in a phone interview with Rai TV, a pro-Gadhafi station based in Syria. "We will fight until martyrdom."

Ibrahim effectively claimed victory in Bani Walid , which along with Sabha and Sirte are the few major municipalities not yet under opposition control.

"Bani Walid is cleansed and the bodies of the NATO gangs are thrown in (the nearby) valleys and mountains," he said.

CNN's Mohamed Fadel Fahmy and Mohammed Tawfeeq contributed to this report.