A mysterious disease has killed nine people in Liberia, leading the health authorities to issue guidelines to citizens on what to do as they investigate the illness.

The BBC reports that the Chief Medical Officer confirmed the deaths and added that another eight persons were in isolation.

The authorities are conducting tests into blood samples and other specimens of the deceased as part of efforts to confirm whether or not the tests are related to the deadly Ebola virus.

Some symptoms of the disease according to reports include: abdominal pains, vomiting and headaches.

Liberia was recently declared free of Ebola by the World Health Organization (WHO). When Ebola broke out in 2015 it killed an estimated 5,000 people and almost shutdown the country.

A United Nations memo also confirmed the deaths with the global outfit warning all its staff over the deaths.

In June last year the WHO declared Liberia free of active Ebola virus transmission, the last of four West African countries at the epicentre of the world’s worst outbreak of the disease.

Traces of Ebola can hide in survivors’ bodies long after they have recovered, but health experts say the risk of Ebola re-emerging and being transmitted to others is extremely low. Despite that, there is a great deal of stigma around survivors of the virus in West Africa.

The epidemic killed more than 11,300 people and infected some 28,600 from 2013, as it swept through Guinea, Sierra Leone and Liberia, according to WHO data.