Health officials say a teenage boy has died from Ebola in Liberia, becoming the country's first fatality from the disease in nearly six months.
The 15-year-old, from a suburb east of the capital, Monrovia, was diagnosed with the virus last week. His father and brother have also tested positive for Ebola and have been taken to an treatment center outside of Monrovia along with three other family members.
Liberian officials have put more than 150 people under surveillance who might be at risk for the disease including health care workers and others who came in contact with the family.
The new cases are a setback for the West African country, which had been declared free of the disease.
Liberia had been Ebola-free since September 3. It was first declared Ebola-free May 9 by the World Health Organization, but new cases emerged in June.
The head of the WHO's Ebola response team, Bruce Aylward, said it is not clear how the boy contracted Ebola. He said the child and his family had no known history of contact with a survivor or victim of the disease.
Liberia is one of three West African countries hit hard by the Ebola outbreak that began in December 2013, recording more than 10,000 cases and more than 4,800 deaths.
The epidemic has killed about 11,300 people, mainly in Liberia, Guinea and Sierra Leone.
The new Ebola cases in Liberia come less than a week after Guinea said it had no more Ebola patients and began the 42-day countdown — twice the incubation period of the virus — to be declared Ebola-free.
Sierra Leone was declared Ebola-free earlier this month.