TRIPOLI AND CAIRO - On Saturday, fighters loyal to Libya's transitional rulers intensified their rocket and artillery attacks against Sirte, one of fugitive leader Muammar Gadhafi's last strongholds, according to military commanders.

Interim government troops have reported major advances since Friday, when they began what they call a final onslaught on the city.

The port city's university and a big tent in which Gadhafi used to hold meetings were both claimed to have been captured. "We will resolve the battle in our favor within days or a week at most," said Makhlouf al-Farjani, a field commander of the interim authority forces in Sirte.

Anti-Gadhafi fighters were trying hard to flush out snipers holed up inside tall buildings in Sirte, on the Mediterranean coast, Al Jazeera reported, quoting an anti-Gadhafi commander. The snipers have proved to be a key obstacle to the rebels' advance.

The capture of Sirte, which is 400 kilometers south-east of the capital Tripoli, would boost the morale of Libya's transitional rulers, who have delayed announcing an interim government until all of Libya is "liberated."

"Fierce battles are now raging between the revolutionaries and the Gadhafi battalions and mercenaries in Sirte," the head of the country's National Transitional Council, Mustafa Abdel Jalil, said.

"Our revolutionaries are trying to stop the snipers positioned on the rooftops of the buildings," he added at a press conference in Tripoli with the British and Italian defense ministers.

Meanwhile, British Defense Secretary Liam Fox said NATO would continue its military operations in Libya until "the remnants" of the Gadhafi regime had been eliminated. "We are careful not to damage the civilian infrastructure," he told reporters in Libya.