A second person has died of Ebola in the border city of Goma in the Democratic Republic Congo.
The lakeside city of more than two million people is a key transport hub close to the Rwanda border, raising fears the deadly illness could spread.
The death toll from the current outbreak has reached 1,790.
Congolese health officials said the latest case involves a man from a northeastern rural community, who arrived in Goma on 13 July and was later diagnosed.
Congolese health officials said that "all measures are being taken to strengthen surveillance at points of entry and sanitary control", amid concern the virus could spread to neighbouring countries.
Efforts to contain the virus have repeatedly been hindered by mistrust of health officials and militia violence, particularly in rural areas.
"Our response teams have just detected and isolated a second case on July 30, 2019. It is initially not being linked to the first case," said an official statement, signed by Congolese professor and leading Ebola researcher Professor Jean-Jacques Muyembe.
According to the statement, the patient was being treated in the Goma Ebola treatment centre after arriving in the city from a mining area of Ituri province.
Earlier this month, a pastor tested positive and later died after arriving in Goma by bus, sparking fears the disease could spread quickly through the densely populated city.
In mid-July, the World Health Organization declared the outbreak a "public health emergency of international concern" - a rare designation only used for the gravest epidemics.
The Ebola virus is highly contagious and has an average fatality rate of around 50%.
It is transmitted to humans from wild animals and spreads among people through close contact with the blood, body fluids, secretions or organs of an infected person.