A hunt has been launched in Sierra Leone's capital, Freetown, for a woman with Ebola who was forcibly removed from hospital by her relatives.
Radio stations around the country are appealing for help to find the 32-year-old who is being described as a "risk to all".
She is the first Freetown resident to have tested positive for the virus.
Meanwhile, Nigeria's health minister has confirmed that a Liberian man has died of Ebola in Lagos.
According to the Reuters news agency, he collapsed on arrival in Lagos on Sunday and was taken from the airport and put in quarantine at a hospital in the Nigerian city.
Since February, more than 660 people have died of Ebola in West Africa - the world's deadliest outbreak to date.
It began in southern Guinea and spread to Liberia and Sierra Leone. The case in Nigeria is the first in Africa's most populous country.
The virus kills up to 90% of those infected but if patients receive early treatment, they have a better chance of survival.
It spreads through contact with an infected person's bodily fluids.
WHO: Latest West Africa Ebola outbreak figures
- Guinea - 314 deaths, 415 cases
- Liberia - 127 deaths, 224 cases
- Sierra Leone - 219 deaths, 454 cases
Sidi Yahya Tunis, a spokesperson for Sierra Leone's ministry of health, said the King Harman Road Hospital was stormed by the Ebola patient's family on Thursday.
The BBC's Umaru Fofona in Freetown said the woman, who is an apprentice hairdresser, is a resident of the densely populated area of Wellington in the east of the city.
The Ebola cases in Sierra Leone are centred in the country's eastern districts of Kenema and Kailahun, just over the border from the Guekedou region of Guinea where the outbreak started.
Our reporter says there is increasing anger and confusion over the handling of the outbreak.
Police say thousands of people have taken to the streets of Kenema to protest - thronging to the town's hospital, which treats all Ebola cases in the district.
The father of a nine-year-old boy has told the BBC that his son was shot and injured by police as they tried to put down the angry demonstration, in which he says his son was not involved.
Our reporter says the police have not been able to confirm this as they say they are still busy with operational matters.
Nurses at Kenema hospital went on strike for a day on Monday after three of their colleagues died of suspected Ebola.
Earlier this week, it was announced that the doctor leading Sierra Leone's fight against Ebola was being treated for the virus.
On Thursday, the World Health Organization said that 219 people had died of Ebola in Sierra Leone.
Ebola virus disease (EVD)
- Symptoms include high fever, bleeding and central nervous system damage
- Fatality rate can reach 90%
- Incubation period is two to 21 days
- There is no vaccine or cure
- Supportive care such as rehydrating patients who have diarrhoea and vomiting can help recovery
- Fruit bats are considered to be the natural host of the virus