Sudan is facing a “huge biological risk” after militants took control of a public laboratory holding samples of deadly pathogens, including polio, cholera, and measles, warns Dr. Nima Saeed Abid, the World Health Organization’s (WHO) representative in the West African nation. The lab’s technicians are currently unable to access the facility to secure the infectious materials, making it an “extremely, extremely dangerous” situation, says Abid.

The lab, which is a partnership between the Sudanese government and various international aid organizations, including the WHO, had been coordinating COVID-19 testing at Khartoum’s international airport. It is now occupied by militants, and there is no accessibility for lab technicians to safely contain the biological material and substances available, warns Abid.

The situation in Sudan has been volatile since fighting broke out between the Sudanese military and forces controlled by a military junta on April 15. At least 427 people have been killed, and 3,700 have been injured since then, according to recent figures from the WHO. The conflict has displaced thousands of people, hampering access to healthcare, basic supplies, and fuel. The WHO has confirmed 14 attacks on healthcare facilities, killing eight people, and 20 hospitals have been forced to close due to a lack of resources.

The National Public Health Laboratory is one of the main areas of clashes, with militants occupying the facility, according to Reuters. While a 72-hour ceasefire is currently in place, it is unclear how effective it will be or how long it will hold. Heavy gunfire and explosions could still be heard across Khartoum after the ceasefire agreement, according to the Associated Press.

The lab’s seizure poses a significant risk to the public health of the country, and it is unclear when or how the situation will be resolved. The WHO and various international aid organizations continue to monitor the situation closely, and many Western nations are working to evacuate their citizens from Sudan.