Health officials were combing Monrovia's West Point area that is home to at least 50,000 people to try to stop the virus from spreading further in a country where more than 400 people already have died.
The World Health Organization on Monday urged Liberia and other Ebola-affected countries to screen all passengers leaving international airports, sea ports and major ground crossings.
Those with symptoms of the virus also were urged not to travel. Many airlines have halted services to the capitals of Liberia and neighboring Sierra Leone.
The weekend chaos in Monrovia highlights the growing unease and panic in Liberia amid the mounting Ebola death toll and illustrates the risks of further instability in this deeply impoverished country where mistrust of the government runs high. In addition, health workers are complaining about a lack of protective gear. Treatment centers are viewed by many as a place where people go just to die.
"They are not happy with the way Ebola is being managed and the response that the government is providing," said Koala Oumarou, country director for the aid group Plan Liberia, which is helping the health ministry to raise awareness. "It's where the frustration is coming from."
Liberia's president already has declared a state of emergency, dispatching armed soldiers to enforce quarantines of infected areas. But little was done Saturday to stoop looters from invading the Ebola quarantine center and taking items covered in bodily fluids that now could only further transmit the gruesome virus, witnesses said. Ebola is spread through direct contact with the blood, vomit, feces or sweat or sick people.
"This West Point situation really was our greatest setback since we started this fight, and we are working on making sure that we can correct that situation," Liberian Information Minister Lewis Brown told The Associated Press.
"We have learned a bit of bitter lesson here," he added.
Witnesses say an angry mob attacked the West Point facility, a "holding center" for people who had been exposed to Ebola and were being monitored during an incubation period for signs of the disease. The looters took medical equipment, and mattresses and sheets that had bloodstains, said a senior police official, who insisted on anonymity because he was not authorized to speak to journalists.
"All between the houses you could see people fleeing with items looted from the patients," the official said, adding that he now feared "the whole of West Point will be infected."
Witnesses said the weekend mob was angry about possible Ebola patients being brought into their area. None of those who fled had yet been confirmed to have Ebola, Assistant Health Minister Tolbert Nyenswah said.
The ransacking of the holding center is only the latest sign of anger among Liberians with the government's response to the crisis. Some health workers and burial teams also have faced aggression from communities who fear the corpses will sicken them. Others have held protests when bodies left on the streets have not been collected fast enough.
This year's outbreak marks the first time the gruesome disease has made its way to Liberia, presenting a herculean task for the aid workers trying to halt its spread through awareness campaigns. Despite the billboards and radio jingles, fear and denial have obstructed efforts to get the crisis under control, observers say.
Liberia is now the country with the highest number of Ebola deaths in the affected West African countries — 413 as of last week — and most believe even that figure is vastly under-estimated. Some of the hardest-hit areas of the country are under quarantine, and many victims are dying uncounted in their own homes, aid workers say.
On Monday, police in riot gear provided security at a new treatment center being operated by Doctors Without Borders, which is also known by its French acronym, MSF.
Lindis Hurum, MSF's project coordinator in Liberia, has described the conditions on the ground there as "catastrophic."
"I think it needs a massive intervention from the international community," she said Monday of the mounting crisis. "This is something that goes way beyond the Liberian government and local authorities, and beyond what MSF can do. The scale is so big now and I think it will get even worse than it is today."