Defense Minister Daniel Chea claimed the death toll was well over 600 people, but there was no way to independently confirm the figure. Aid groups and hospitals have put the number of dead above 90, but say they expect the number to rise.
"Last night, we counted about 65 dead," CBS News' Stefan Faris reported from Monrovia. "That's including only those people that were brought dead to the hospital or those deposited at the gates of the American embassy as a form of protest. So the true number is probably somewhere between that 65 and that 600."
In a phone interview with The Associated Press on Monday, embattled Liberian President Charles Taylor repeated his call for a promised West African peacekeeping force to arrive quickly to "bring some sanity" to the nation founded by freed American slaves.
But Taylor said the best way to ensure stability was through U.S. troops on the ground, in addition to the Marines guarding the U.S. Embassy. "An American contingent would be excellent."
Speaking to reporters at his ranch in Crawford, Texas, Monday, President Bush indicated he had not yet decided the size of a U.S. force that might be sent to help a promised West African peacekeeping mission in Liberia.
"We're monitoring the situation very carefully," he said.
But sources tell CBS News Mr. Bush is in no hurry to put these troops on the ground in Liberia; he wants them to go in as "peacekeepers, not peacemakers."
U.S. officials announced that 4,500 more American sailors and Marines have been ordered to position themselves closer to Liberia, if needed for an evacuation of Americans, peacekeeping or some other mission.
Meanwhile, a storm of mortars rocked residential neighborhoods along with two U.S. Embassy compounds in the rebels' third attempt to take Monrovia — Taylor's last stronghold. An American journalist was among the injured.
American helicopters landed in the Embassy compound in a driving rain Monday, dropping off about half of a 41-member Marine security team. The troops, who were sent to beef up security at the embassy, evacuated about 23 foreign humanitarian workers and journalists.
Clutching bags and backpacks, the evacuees ran to the spinning aircraft as Marines and embassy officials shouted: "Go! Go!" Among them were the United Nations' last seven foreign staffers, who had returned to Monrovia just two weeks earlier during a lull in fighting.
The State Department criticized the rebel group Liberians United for Reconciliation and Democracy for "reckless and indiscriminate shooting" and appealed to neighboring African countries to guard against weapons going to Liberia.
Joe Wylie, a rebel delegate at peace talks in Ghana, said the government was also firing shells.
The rebels were "not responsible for shooting mortars into the embassy," Wylie said. "We have our backs to the U.S. Embassy. ... They (government forces) were shooting at us."
During 2½ hours of sustained mortar fire, a shell slammed into a U.S. Embassy residential compound where some 10,000 terrified Liberians had taken refuge, killing 25 people, aid workers said. Many more were wounded, including two Liberian embassy guards.
After the blasts, enraged Liberians dragged bodies from the residential compound and lined them up in front of the embassy, next to a wall emblazoned with the American seal. The group demanded to know why Washington has not sent troops to end more than a decade of strife in the West African nation.
"We're dying here," screamed some in the crowd, as two American servicemen in camouflage watched from behind bulletproof glass.
One man held up a hastily scrawled sign: "Today G. Bush kill Liberia people."
More than 360 people were injured — some hauled to the hospital in wheelbarrows, others screaming in pain. Monday appeared to be the bloodiest in two months of fighting by rebels attempting to seize the capital.
Among the injured, Tom Masland, an American who is Newsweek's African regional editor, was hit in the arm by shrapnel.
U.N. Secretary-General Kofi Annan once again urged Washington and West African states to commit troops.
"I think we can really salvage the situation if troops were to be deployed urgently and promptly," he said.
Taylor has pledged to resign and accept an offer of asylum in Nigeria — but only after peacekeepers arrive to ensure an orderly transition. But in his interview with the AP, he also hinted he might make other demands of Mr. Bush before agreeing to step down.
"I have written him a letter outlining to him certain things that are necessary for me to step down and certain things that are necessary for me to leave the country," said Taylor, without elaborating.
Bush has said any deployment of U.S. troops is conditional on the departure of Taylor, a former warlord indicted for war crimes in Sierra Leone, where he supported a brutal rebel movement.
Taylor launched Liberia's last civil war in 1989, emerging in 1996 as the strongest warlord. He was elected president the following year, and now faces rebels who include former rivals from the earlier war.