Eight bodies, including those of three journalists, were found after an attack on a team trying to educate locals on the risks of the Ebola virus in a remote area of southeastern Guinea, a government spokesman has said.
"The eight bodies were found in the village latrine. Three of them had their throats slit," Damantang Albert Camara told Reuters on Thursday.
The gruesome discovery came as the World Health Organisation (WHO) said more than 700 more Ebola cases had emerged in West Africa in the past week.
The UN health agency said on Thursday that more than 5,300 people had contracted the virus, and that the latest statistics showed that just under half of these cases were recorded in the last three weeks.
Rain or shine, the shutdown exercise is going to go ahead. During the three days ... the job is going to get done.
Just three weeks ago the number of new cases was about 500 for a one-week period.
The death toll also passed 2,600 people, an increase of roughly 200 from the last estimate, WHO said.
Later on Thursday, the UN Security Council declared the outbreak a "threat to international peace and security" and called on all states to provide urgent resources and assistance to help tackle the crisis.
The alarm came as Sierra Leone readied for an unprecedented three-day nationwide lockdown to contain the spread of the Ebola, in a controversial move which experts claimed could worsen the epidemic.
The population of six million will be confined to their homes from midnight on Thursday as almost 30,000 volunteers go door-to-door uncovering patients and bodies hidden in people's homes.
"Rain or shine, the shutdown exercise is going to go ahead. During the three days ... the job is going to get done," said Steven Gaojia, head of the government's emergency operation centre.
RELATED: Sierra Leone economy hit by Ebola travel ban
The worst outbreak so far of Ebola has claimed more than 500 lives in Sierra Leone, one of three countries at the epicentre of the epidemic.
"Ose to Ose Ebola Tok" - "house-to-house Ebola talk" in the widely-spoken Krio language - will see more than 7,000 volunteer teams of four visiting the country's 1.5 million homes.
They will hand out bars of soap and information on how to prevent infection, as well as setting up "neighbourhood watch"-style community Ebola surveillance teams.
The government has said the teams will not enter people's homes and are not tasked with collecting patients or bodies, but will call emergency services or burial teams "if by chance the teams happen to bump into such situations".
Extra beds have been set up at schools and hospitals across the country, including 200 around Freetown, with the government projecting a 15 to 20 percent upsurge of cases as new patients are discovered.
Community activists and civil society leaders have been recruited to help thousands of police and soldiers enforce the curfew.