The prime minister of Guinea said that seven bodies had been found after a team of health workers went missing during a push to raise awareness of the outbreak of Ebola which started in the country nine months ago.

Witnesses said the team were set upon by angry residents in the remote village of Womey, where many remain in denial about the disease, or suspicious of foreign health workers. Several failed to return following the visit on Tuesday. Officials earlier said some – including three journalists and the director and two senior doctors of the main local hospital – were being held captive. Atempts to reach them stalled when angry residents destroyed bridges leading to the village.

"The meeting started off well; the traditional chiefs welcomed the delegation with 10 kola nuts as a traditional greeting," said a resident who was present at the meeting and gave only his first name, Yves. "It was afterwards that some youths came out and started stoning them. They dragged some of them away, and damaged their vehicles."

In an announcement made on state television late on Thursday, Mohamed Saïd Fofana said authorities had located the bodies a day after the group was abducted. Among the dead were three Guinean radio journalists who had been covering the education efforts.

A government spokesman, Damantang Albert Camara. told Reuters: "The bodies were found in the village latrine. Three of them had their throats slit." Some others from the delegation are still believed to be missing.

The Ebola outbreak across five west African countries has spiralled into the world's biggest ever epidemic, with more than 700 cases – out of 5,300 overall – emerging in the past week alone, the World Health Organisation said on Thursday.

The WHO said there was a desperate shortage of health workers and supplies in an epidemic likely to last many more months. Health workers across Guinea, Liberia and Sierra Leone, where most of the cases are, have been periodically attacked by citizens in a region experiencing the deadly virus for the first time.

The district of Nzérékoré, where the team disappeared, exploded in clashes after health workers tried to spray the local market last month. About 50 people were arrested and two dozen police officers who were sent to quell the riots were injured.

In Sierra Leone, almost 30,000 volunteers will go house-to-house to raise awareness of the disease during a three-day "lockdown", when residents have been asked to remain at home. Thousands of soldiers are to enforce the curfew, due to start at midnight on Thursday.

A sluggish international response to the crisis has picked up in recent days. The US will send 3,000 troops to Liberia to help provide desperately-needed boots on the ground in the country hardest hit by the outbreak.

France's president, François Hollande, said the former colonial power would set up a military hospital to help tackle the disease in Guinea.