At least 80 inmates and 18 guards were injured in "disturbances" at a severely overcrowded prison in the Chilean capital, an official said.
That tally was provided to reporters by guards at Santiago's ex-Penitenciaria prison, although the head of the prison guard service, Luis Masferrer, said 54 inmates and 12 guards suffered injuries of varying degree on Wednesday night.
He also ruled out reports of a riot, contradicting statements by prison guards.
"This shouldn't be referred to as a riot. Instead, there were disturbances inside the prison. We activated all the alarms and the important thing is that security inside the penal facilities corresponds to the prison guard service," La Tercera daily reported, citing Masferrer.
"The crisis of the prison system is an everyday problem. There are 7,115 convicts at this prison and it was designed for 2,900," he said.
At least 300 guards were involved in controlling the disturbances, officials said, adding that none of the inmates suffered serious injuries.
Seven fire trucks also were deployed to the facility due to reports of a blaze.
This latest incident comes one week after a prison brawl and subsequent fire at Santiago's San Miguel penitentiary, which also suffered from severe overcrowding, left 81 inmates dead.
The prison where Wednesday night's disturbances occurred is located a short distance from Santiago's traditional O'Higgins Park and some 20 blocks from the La Moneda presidential palace, while the San Miguel prison is situated seven km from the capital's downtown.
Several of the guards injured Wednesday were taken to the Carabineros (Militarized Police) Hospital, while the wounded inmates were treated at the penitentiary's infirmary.
Masferrer said the violent incidents stemmed from protests over a routine raid of the facility to confiscate prohibited items such as cellphones. Anti-riot forces were deployed to quell the disturbances, he said.