A fire set by feuding inmates raged through a cellblock at a prison southeast of Buenos Aires (search) early Sunday, killing 32 inmates and leaving two jailers injured, authorities said.

All the deaths appeared to have been caused by asphyxiation after inmates were overcome by smoke, said Justice Minister Eduardo Di Rocco of Buenos Aires province, where the prison is located.

Di Rocco said inmates first began fighting just before midnight and then set mattresses and blankets alight. The fire spread through one of several cellblocks in the sprawling prison in Magdalena, 45 miles southeast of Buenos Aires.

Speaking on the prison grounds, Di Rocco added that it was unclear what caused the disturbance but he rejected initial reports that a demand for more visiting hours for relatives led up to the blaze. He said the fire was contained to one unit known as Pavilion 16.

"Unfortunately, I must announce there were 32 deaths," Di Rocco said.

He said the warden rushed to the scene and was critically injured by a blow to the head and had to be hospitalized along with a second jailer. During the fight, authorities said, a kitchen area and a workshop were torched.

Di Rocco had no information on survivors other than to say 16 others in the unit would be interrogated to determine the exact chain of events. He said forensic experts were trying to identify the dead.

Earlier Sunday, some 500 relatives anxiously massed outside the prison, demanding to know about their loved ones. The fire occurred on the date Argentines traditionally celebrate Mothers' Day, and many women had gone to the prison to see imprisoned relatives.

Earlier, television network Todo Noticias (search) showed women shouting insults at riot police guarding the main entrance. The family members were demanding a full accounting of the dead and injured.

Some of the relatives briefly scuffled with police, who held them back with shields before jailers later calmed the crowd and allowed visitors to begin entering other areas of the prison, which houses more than 800 inmates.

The independent news agency Noticias Argentinas (search) quoted a prison official identified as Sebastian Cornutta as saying the dead were taken to a prison chapel.

Fires and riots are common in Argentina's crowded prison system. On Feb. 10, rioting at the San Martin penitentiary in the central Argentine province of Cordoba caused eight deaths. During that rampage, a warden and two dozen guards were taken hostage.