The crisis affecting prisons, although particularly bad in the impoverished state of Maranhão, is also being felt - and has led to a large number of deaths - in the richer areas of Brazil, including the southern state of Rio Grande do Sul, O Globo newspaper said Wednesday.

The daily published a judicial report concerning 23 inmate deaths in the Presidio Central in Porto Alegre, the capital of Rio Grande do Sul, since January 2010.

Though all of the deaths were attributed to natural causes, Judge Sidnei Brzusca found that at least five of them have "indications" that they were homicides, O Globo said.

The deaths under scrutiny always occurred with the same characteristics: young inmates with no history of cardiovascular illness dying of heart attacks or pulmonary edema always early in the morning and with evidence of cocaine in their bloodstreams.

Porto Alegre's Presidio Central is a notoriously dilapidated complex that suffers from especially high levels of overcrowding.

In the first week of January, the Inter-American Court of Human Rights warned the state government that it must take a series of measures to improve conditions in that particular prison.

The most serious prison crisis in the country, however, is the one in the state of Maranhão, where 62 inmates have been murdered since January 2013.

The violence in the prisons has extended to the streets of the state capital, Maranhão city, where criminal groups operating from behind bars at the beginning of January ordered attacks on public buses in retaliation for the stationing of militarized police inside penitentiaries. EFE