Fears have been raised that samples of Ebola viruses could escape from a laboratory in the Democratic Republic of Congo after violence erupted in the country.
The facility is in the strategic city of Goma, eastern Congo, which Rwandan-backed rebels claim to have captured.
The International Committee of the Red Cross has voiced concern over the risk of fighting near the laboratory, warning the consequences would be “unimaginable”.
The organisation said the lab housing the samples had lost power due to the fighting, jeopardising the samples.
Ebola is a rare but severe illness that is often fatal and is spread through physical contact.
Outbreaks of the virus have occurred in central and west Africa, with the Democratic Republic of Congo being one of the countries that most recently experienced a surge in cases.
The disease has never been spread from person to person in the UK.
Fierce fighting has raged between the Rwandan-backed M23 group and Congolese Government forces, and there is concern the conflict could spill over into a regional war.
The UN has warned civilians caught up in the heavy fighting face a “critical” 24 hours, with food and water running low and aid unable to enter.
The spokesperson for the UN’s aid coordination office said colleagues in the country have reported heavy, small arms fire and mortar fire across Goma and “many dead bodies in the streets”.
Jens Laerke said: “We have reports of rapes committed by fighters, looting of property, including of a humanitarian warehouse and humanitarian and health facilities being hit.”
The UN Security Council met in New York on Monday, where ambassadors called for an immediate halt to M23’s offensive and called on the group to withdraw from the territories it has seized.
The council also condemned the presence of “external forces” amid reports that Rwandan troops were involved in the offensive.
More than a dozen UN peacekeepers have been killed in the country during the violence.
