Nigeria is warning people against fake coronavirus vaccines as there are reports that some are in circulation.
On Friday Nigeria's National Agency for Food Drug and Administration Control urged the public to be aware.
It said fake vaccines can cause "Covid-like illnesses or other serious diseases that could kill."
It also said no vaccine had been approved by the body.
10 million real doses of the vaccines are expected in March, authorities are working on which one.
It was also unclear whether the batch would be financed by the African Union (AU) or as part of COVAX, which links the World Health Organization (WHO) with private partners to work for pooled procurement and equitable distribution.
Last year, black market coronavirus tests flourished in Nigeria because citizens were reluctant to be subjected to mandatory quarantine.
Nigeria has said it hopes to vaccinate 40 percent of the population in 2021.
But the challenges of transporting and storing vaccines for many millions of people are enormous in a country where adequate hospital facilities are lacking.
Nigeria is the most populous nation in Africa and has officially reported some 104,000 COVID-19 cases with more than 1,300 deaths.
But the real toll is expected to be higher as the number of tests is low.
Cases have risen sharply since the end of November, notably in the economic capital Lagos, a city of about 20 million people. The death rate has also increased.
A variant strain of coronavirus has been discovered in recent months but it remains unclear whether it is more contagious or deadly.