Human rights groups want an investigation after 46 people died in a riot at a Venezuelan prison.
The country’s prisons minister, Iris Varela, said the riot followed a failed escape attempt by inmates and that the prison’s director was among 75 people injured.
But opposition politician Maria Beatriz Martinez blamed a new ban on inmates receiving food from their relatives.
This had been customary in Venezuelan prisons but was stopped as part of Venezuela’s effort to prevent the spread of COVID-19.
The UN’s Office of the High Commissioner for Human Rights said on Twitter that it was “gravely concerned” about the riot.
It added: “We urge the authorities to conduct a thorough investigation, tackle overcrowding, and guarantee basic rights.”
Venezuela is among a number of South American countries where prisons are well-known for poor conditions and violence.
Los Llanos penitentiary in Portuguesa state, where the latest riot was, was built for around 750 inmates but currently has at least 2,500, according to the Venezuelan Observatory of Prisons.
The group’s president Beatriz Giron said she did not believe the National Guard’s explanation – that a group of armed prisoners had tried to break out of the jail’s main entrance.
“It is difficult to believe that at 1pm, in the light of day, prisoners are going to escape through the front door,” she added.
Venezuela’s information ministry and chief prosecutor’s office both failed to respond to requests for comment.