(CNN) Forgetting those behind bars as coronavirus cases continue to surge in Europe and the US could be "potentially catastrophic," UN High Commissioner for Human Rights Michelle Bachelet says.
"In many countries, detention facilities are overcrowded, in some cases dangerously so. People are often held in unhygienic conditions and health services are inadequate or even nonexistent. Physical distancing and self-isolation in such conditions are practically impossible," Bachelet said in a statement.
Governments across the world should take urgent action to slow the spread of the virus within facilities including jails and prisons, immigrant detention centers, residential care homes, psychiatric hospitals and orphanages.
"It is vital that governments should address the situation of detained people in their crisis planning to protect detainees, staff, visitors and of course wider society," she said.
In Colombia, fears over the virus prompted a violent prison riot that left at least 23 inmates dead and more than 80 injured, the country's Ministry of Justice said.
There was a "massive and criminal escape attempt" at the Bogota's La Modelo prison, one of the country's largest and most overpopulated prisons, Justice Minister Margarita Cabello said in a video address.
Other facilities saw revolts too, Cabello said.
In Italy, inmates overran more than 20 prisons, escaping their facilities and kidnapping officers, after visitors were banned in efforts to curb the spread of the virus, the country's Ministry of Justice said in a statement. Multiple inmates died.
Earlier this week, the World Health Organization (WHO) released guidance on how prisons and detention facilities should work to prevent cases and slow the spread of coronavirus.
"To effectively tackle a Covid-19 disease outbreak in prisons, state authorities need to establish an up-to-date coordination system that brings together health and justice sectors, keeps prison staff well-informed, and guarantees that all human rights in the facilities are respected," the agency said.
Meanwhile, several communities across the US moved to downsize incarcerated populations.
New Jersey announced earlier this week that it would be releasing about 1,000 low-level offenders from its jails to combat spread of the virus. New York City said it would be releasing inmates convicted of misdemeanors and nonviolent felonies who had less than a year left to serve, Mayor Bill de Blasio said.
And California Gov. Gavin Newsom announced he had signed an order which restricted placing or transferring inmates into the state's prisons and youth correctional facilities for the next month.
"Now, more than ever, governments should release every person detained without sufficient legal basis, including political prisoners and others detained simply for expressing critical or dissenting views," Bachelet, with the UN, said in her statement.
In Texas, prison visits to the state's 140,500 inmates have been suspended.
The Texas Department of Criminal Justice also said it was limiting gatherings to ten people or less in all areas, including the dining halls and inmate classes.
"Restrictions on visits to closed institutions may be required to help prevent Covid-19 outbreaks, but such steps need to be introduced in a transparent way and communicated clearly to those affected. Suddenly halting contact with the outside world risks aggravating what may be tense, difficult and potentially dangerous situations," Bachelet said.
Bachelet said she was "deeply concerned" that some countries were threatening prison time for residents who didn't comply with the measures set to combat spread of the virus.
In Jordan, -- which implemented one of the world's strictest lockdowns -- for example, security officials said more than 1,600 people had been arrested by Monday for violating the curfew that was put in place Saturday. Those offenders face up to a year in prison. The country has since eased its lockdown and loosened restrictions.
"Imprisonment should be a measure of last resort, particularly during this crisis," Bachelet said.