The coronavirus has breached the walls of DR Congo prisons with potentially catastrophic consequences for the overcrowded facilities, charity groups say.
On Thursday and Friday, 43 prisoners tested positive for COVID-19 at the Ndolo military prison in central Kinshasa, Africa's third largest city with at least 10 million inhabitants.
"Tests of all detainees are in progress," according to the latest bulletin by health authorities.
The prison holds 1,900-2,000 prisoners, according to different sources.
The Democratic Republic of Congo has registered 10-20 new cases of the virus per day since it was first detected there on March 10.
The nation has reported 604 cases in all, mostly in Kinshasa, and 32 deaths.
Health Minister Eteni Longondo wants to isolate those infected in the prison and sanitize the cells.
He said that "a woman who brought food" had introduced the virus into the prison.
In mid-April, the non-governmental organisation Human Rights Watch (HRW) warned that "the Democratic Republic of Congo's overcrowded and unsanitary prisons are at grave risk of COVID-19 outbreaks."
HRW, citing figures by the UN peacekeeping mission MONUSCO, said: "Congo's main prisons are at 432 percent of capacity."
The prison in Goma had an even higher rate of 600 percent, it added.
The group published photos said to show prisoners sleeping on the floor in a cell at the Makala prison in Kinshasa, at 461 percent of capacity.
It quoted a recently released prisoner as saying that "there were at least 850 of us in a space with a capacity for 100 people."
He added that "the situation is worse in some of the other wings. If the coronavirus reaches Makala, there will be no one left."
According to the health ministry no COVID-19 cases have been detected at the prison to date.
In early January at least 11 prisoners died there from a lack of food and medication, a penitentiary source told AFP.
Other sources say up to 25 people had died.
Each year, hundreds of detainees die in Congolese prisons from starvation and lack of care.
"The quantity of food is not even enough for a two-year-old" according to Augustin, a prisoner on death row in Agenga, northwestern DRC cited by the NGO Ensemble in a report published in December.
It also reported a shortage of medication with the exception of paracetamol and treatments for malaria and tuburculosis,
In addition, the prison in Goma had only three toilets for 500 detainees, it said.
There are around 500 people who have been sentenced to death in the country, which suspended capital punishment in 2003.
They are in contact with the rest of the prison population, "around 71 percent of which still await trial," HRW said.
Justice Minister Celestin Tunda said, "at least 1,200 detainees" had been released "to slow the spread of the coronavirus" and that more were expected to be freed next week.
But the Congolese NGO Justicia accused the government of "notorious negligence" in the case of those infected at the Ndolo prison and insisted it "do something to avoid a hecatomb".