Seven people believed to have the Ebola virus have died in recent days in the first deaths reported in the Liberian capital since the outbreak began, a health official said on Tuesday.

Deputy Health Minister Tolbert Nyenswah told AP news agency the latest deaths brought to 16 the number of people believed to have died from the virus in the West African country. Four of the deaths were confirmed by tests to be Ebola, Nyenswah said on Tuesday.

The deaths, recorded since June 8, are worrying because no new cases had been confirmed in Liberia in almost two months. Nyenswah said the new wave of cases was believed to have emerged on May 30.

The virus, which causes severe bleeding and high fevers, has continued to ravage neighbouring Guinea and has spread to Sierra Leone.

"The first phase of the epidemic was contained,'' said Nyenswah. "But because of proximity to Guinea and Sierra Leone, we did not declare the outbreak over."

Other officials have previously downplayed the significance of the virus jumping borders, saying that it was to be expected since people travel and trade frequently across the borders of the three countries.

Staff flee hospital

One of the seven deaths was a woman who had recently travelled from an infected area in Sierra Leone and is believed to have passed the disease on to others in the house where she was staying in Monrovia.

At one hospital on the outskirts of Monrovia, staff and patients fled after the death on Saturday of a nurse. On Tuesday, President Ellen Johnson Sirleaf visited the hospital and met with a few nurses who came back to the hospital to mourn their colleague. But the beds were still empty and most of the staff have stayed away.

The outbreak appears to have begun in neighbouring Guinea, where the vast majority of the cases and deaths have been recorded. Amara Jambai of Sierra Leone's Ministry of Health said on Tuesday that the number of confirmed deaths from Ebola in his country had risen to 20 in recent days.

The new deaths reported in Liberia and Sierra Leone would push the World Health Organization's death toll for the current outbreak to more than 250. There is no vaccine and no known cure for Ebola, which causes severe bleeding, although proper care can increase the survival rate.