Medical staff working at a prison in Bukavu in the east of the Democratic Republic of Congo says 45 inmates have died due to lack of care since the beginning of the year.
Some sick prisoners were taken to the city’s main hospital but it reportedly did not have enough drugs to treat them.
Prison health workers have now gone on strike over the lack of medicine and equipment, as well as pay arrears.
There have long been concerns over the conditions in Congolese prisons.
Last June over an 18-month period around 40 inmates had died from malnutrition at a facility in Mbanza Ngungu, south of the capital Kinshasa.