In the sprawling oceanfront West Point neighborhood of Monrovia, at least four people were injured in clashes with security forces, witnesses said.
It was unclear whether anyone was wounded by the gunfire, though a Reuters news agency photographer saw a young boy with his leg largely severed just above the ankle on Wednesday.
Liberian authorities introduced a nationwide curfew on Tuesday and put the West Point neighbourhood under quarantine to curb the spread of the disease, Reuters reported.
"The soldiers are using live rounds," said army spokesman Dessaline Allison, adding: "The soldiers applied the rules of engagement. They did not fire on peaceful citizens. There will be medical reports if (an injury) was from bullet wounds."
The World Health Organization said that the countries hit by the worst ever outbreak of the deadly virus were beginning to suffer shortages of fuel, food and basic supplies after shipping companies and airlines suspended services to the region.
The epidemic of the hemorrhagic fever, which can kill up to 90 percent of those it infects, is ravaging the three small West African states of Liberia, Sierra Leone and Guinea. It also has a toehold in Nigeria, Africa's biggest economy and most populous country.
Liberia - where the death toll is rising fastest - said its ministry of health warehouse had run out of rubber boots and bottles of hand sanitiser, essential for preventing the spread of the disease.
Still struggling to recover from a devastating 1989-2003 civil war, Liberia recorded 95 deaths in the two days to August 18th, the World Health Organization said. Since it was discovered in remote southeastern Guinea in March, the overall death toll from the outbreak has reached 1,350 from a total of 2,473 cases.
Witnesses said the clashes in West Point started after security forces early on Wednesday blocked roads to the neighbourhood with tables, chairs and barbed wire. Residents said they were not warned.