Relatives of inmates at the San Miguel prison react as they listen the list of names of inmates who died in a fire in Santiago, Chile, Wednesday. (AP) SANTIAGO: A fire that began during a riot in a severely overcrowded prison killed at least 81 inmates Wednesday and seriously injured 14 others, officials said. Chileans nationwide could hear the screams of inmates after a prisoner using an illegal cell phone called state television for help. “The conditions that existed inside this prison are absolutely inhumane,” said Chilean President Sebastian Pinera, who visited an emergency center where inmates were being treated for severe burns and smoke inhalation. National prison police director Luis Masferrer said the blaze broke out about 5:30 A.M. (7:30 A.M. EST; 1230 GMT) at the San Miguel prison south of the capital, and it was brought under control about three hours later. Preliminary reports indicated the fire was set intentionally, said investigator Alejandro Pena. Interior Minister Rodrigo Hinzpeter said it started during fighting between inmates and reached its maximum intensity in just three minutes. Firefighters said they were alerted to the fire by a call from a cell phone inside the prison. Santiago region Gov. Fernando Echeverria said the official death toll was 81. Health Minister Jaime Manalich called it an “enormous calamity,” and it appeared to be the worst disaster in the history of Chile's prisons. A fire in a northern prison killed 26 people in 2001. Hundreds of worried and angry relatives of inmates gathered in a chaotic scene outside the gates of the prison, a collection of cement towers that rises above a middle class neighborhood. Some waited six hours before officials read out the names of survivors – which people mistook for those of the dead. Some spat or hurled rocks at Masferrer. Pedro Hernandez, who directs Chile's prison guards union, said there were only five guards to watch over the prisoners. Pinera, however, said there were six guards in the prison towers where the inmates are held, and 26 others stationed at the perimeter.