A brawl at a prison in Russia has injured 20 inmates, prison officials said on February 9.
The fight broke out during dinner on February 8 at the penitentiary in southwestern Samara, officials said.
Mattresses and blankets were set ablaze during the unrest, media reports said, citing prison officials.
Twenty inmates were injured in the mayhem, with 17 requiring hospital attention, prison officials said.
Security at the prison was tightened following the incident. Operations there were reported to have returned to normal on February 9.
Russian prisons have been criticized for their harsh conditions and treatment of inmates.
In November, four guards at a prison in Chelyabinsk were convicted of beating inmate Sultan Israilov to death. Officials wrote his death off as a suicide until a mass hunger strike caused a national outcry and prompted an investigation.
In January, two officials at IK-7 in Karelia were sentenced to prison terms for torturing prisoners and extorting millions of rubles from convicts and their families.
According to statistics provided by Russia to the Council of Europe in 2015 on its prisons for the previous year, 4,097 prisoners died in custody out of a total prison population of 671,027. Of those, 404 were listed as suicides, while the homicide figure was "not available." Russia's mortality rate of 61.1 per 10,000 prisoners was among the highest of the 47 countries studied.
Russia has not provided figures for subsequent Council of Europe reports on prison conditions.