President Charles Taylor (searchvowed to fight "to the last man," as rebels pushed into Liberia's war-ravaged capital and ended hopes that a quick deployment of international peacekeepers could prevent more bloodshed.

Tens of thousands of frightened residents fled the fighting amid machine-gun fire and explosions rang out while others surged toward the clashes waving leafy branches and demanding an end to a decade of violence in this West African nation founded by freed American slaves.

As the battle intensified, fighters wearing shorts and flip-flops traded grenade and machine-gun fire on the two bridges leading into downtown Monrovia (search) from the port area.

"This is where the last fighting will take place. We will not allow them to cross the bridges," Liberia's military chief Gen. Benjamin Yeaten said by phone.

Wearing a gray safari jacket, Taylor spoke on the balcony of his executive mansion overlooking the sea. He repeated his pledge to step down and accept asylum in Nigeria (search), but only after international peacekeepers arrive in sufficient numbers.

The warlord-turned-president vowed to "fight street-to-street, house-to-house" until the rebels are defeated.

"I will never desert the city, I will never desert my people," he told The Associated Press. "I will stand and fight to the last man until they stop killing my own people."

The rebel assault -- the third against Monrovia since last month -- shattered hopes that a speedy deployment of international peacekeepers could avert fresh violence in a country where hundreds of thousands have died in two savage civil wars.

Late Saturday, mortars slammed into the neighborhood surrounding the U.S. Embassy compound.

U.S. Ambassador to Liberia John W. Blaney urged the rebels not to advance further into Monrovia and to refocus on peace talks in Ghana, which seek to reach agreement on a transition government to oversee elections.

"Any lasting peace must be based on a broad political understanding and fighting government forces in Monrovia does not change that fact," Blaney said.

A French news photographer, Patrick Robert, was shot in the chest and arm covering fighting at one of the bridges. Robert, who was on assignment for Time magazine, suffered life-threatening injuries and was being treated at an International Committee of the Red Cross trauma unit in Monrovia, a Time spokesperson said.

Attempts were being made to evacuate Robert.

Rebel officials, in nearby Ghana for peace talks, said government forces provoked them into fighting.

"You lock onto the enemy and when you do, you push him. But he provoked us. We are talking to our commanders and want to stabilize the situation and halt our men," said Joe Wiley of the Liberians United for Reconciliation and Democracy, or LURD, rebels.

Angry residents demanded to know what was keeping a long-promised peacekeeping force they hoped would be led by Americans.

President Bush has repeatedly promised to support West African nations who plan to send 1,500 soldiers to enforce an often-violated June 17 cease-fire. But he says he is still deciding whether to send troops to the country. Bush has tied any deployment of American troops to Taylor's departure.

"If Americans want to help us, this is the time," said Varney Gbassay, as truckloads of fighters armed with AK-47s and grenade launchers raced past his house. "They must not wait until everyone dies."

Taylor also blamed a U.N. arms embargo for the country's plight. The embargo was imposed to punish Taylor's regime for trading guns for diamonds with rebels in neighboring Sierra Leone. Taylor has been indicted by a U.N. tribunal for alleged war crimes there.

"President Bush must take some of the responsibility and the United Nations Security Council for preventing Liberia from being able to defend itself adequately," Taylor said.

Long columns of people hurried toward the city center and eastern neighborhoods with rolled-up mattresses, bundles of clothes and pieces of furniture balanced on their heads. Among them were pro-government militia fighters.

The retreat of hundreds of militia fighters reflected growing unease within Taylor's forces, many of them young men who say they fear being abandoned by the president.

But Taylor said, "My men must understand now that I'm going no place, nowhere, until the international community has sufficiently deployed troops in this country."

Meanwhile, thousands of residents streamed through the streets of a neighborhood housing diplomatic compounds seeking shelter behind their gates.

The U.S. diplomatic residential compound already is crammed with some 10,000 refugees from the two recent rounds of fighting which saw rebels again fighting their way into the city.

Mary Warren, 28, a baby strapped to her back, was among those desperate for entry.

"Anywhere we go they say the place is full. I don't know what to do. Please help me," she said.