Updated

Jubilant revolutionary forces raised their tricolor flag Monday over a convention center in Sirte that served as a base for Muammar Qaddafi's loyalists there, but fighting surged elsewhere in the fugitive leader's hometown.

Col. Younis al-Abdally, a commander in Sirte, said his troops have surrounded pro-Qaddafi fighters in a small area in the upscale Dollar Street. He conceded the final battle is likely to be a fierce one, saying he has information one of Qaddafi's sons and a number of top officials from the ousted leader's regime are holed up in villas in Sirte.

He spoke as tank, rocket and machine-gun fire echoed through the streets around the Ouagadougou Convention Center, an ornate complex that Qaddafi frequently used for international summit meetings.

The capture of the walled complex was a symbolic victory because Qaddafi fighters have used it as a base and stronghold throughout a weekslong siege of the Mediterranean coastal city by forces of the new government.

Revolutionary forces also claimed significant gains in the inland enclave of Bani Walid, after weeks of faltering advances that resulted in part from the challenging terrain of desert hills and steep valleys. Bani Walid is believed to be harboring high level figures from the Qaddafi regime.

Libya's de facto leader, Mustafa Abdul-Jalil, head of the governing National Transitional Council, said Sunday that he expected both cities to be seized within a week. Similar predictions in the past have not been fulfilled.

Heavy fighting raged in Sirte on Monday as fighters pushed through residential areas that have been used as cover for the former regime's snipers.

The transitional leadership, eager to move forward with efforts to hold elections and establish a democracy more than six weeks after seizing control of the capital, has said it will declare that Libya has been liberated after Sirte falls.

A team from the International Committee of the Red Cross entered Sirte's Ibn Sina Hospital Monday to evacuate wounded people left behind after three weeks of fighting.

Abdallah Etbiga, a doctor there, said more than 100 patients, including several wounded children and their families, were trapped in the hospital.

Located 250 miles southeast of Tripoli, Sirte is key to the physical unity of the nation of some 6 million people, since it lies roughly in the center of the coastal plain where most Libyans live, blocking the easiest routes between east and west.

Revolutionary forces launched an all-out assault on Sirte on Friday, pounding the city with tank shells, field cannons, rockets and heavy machine guns. Qaddafi loyalists have put up fierce resistance, firing back with Grad rockets, sniper rifles, mortars and rocket-propelled grenades.

The revolutionary forces also have gained control of the University of Sirte on the city's southern outskirts. As they push forward, Qaddafi loyalists are fighting in an ever-shrinking defensive perimeter consisting only of a Qaddafi palace complex, some residential buildings and a hotel near Green Square in the city center.