Twenty people were killed after a fire tore through a youth home on Wednesday in San Jose Pinula, Guatemala, the country`s National Civil Police said. Video from the scene showed sobbing family members outside the home, banging on the doors looking for loved ones.Nineteen female residents of Virgen de la Asunción Safe Home were killed in the blaze, all of them between the ages of 13 and 17, the National Civil Police told CNN en Espanol. A cook at the home was also killed.The fire, which began around 9 a.m., injured 36 other minors, 11 of them critically, police said.The blaze started when some of the youths in the home set fire to a mattress on their way to breakfast, said Abner David Paredes Cruz, the attorney for Guatemala`s Human Rights office.The facility houses minors who have suffered physical, psychological and sexual violence, or who have mild disabilities. Some residents have been abandoned, addicted to drugs, or been victims of trafficking, the Guatemalan government saidHuman rights groups criticized the home in the past, saying it was overcrowded and was lacking in specialized care for residents."It`s a terrible event, what happened, and more terrible that this could be avoided," Anabella Morfín, Guatemala`s general prosecutor, said.Some parents feared their children were among the dead."I am hurting as a mother because she does not deserve this. I gave her advice. I hope that it is not her," Carolina Juarez, whose daughter was in the home, told AFP.Guatemala`s president has declared three days of mourning, according to a spokesman. The Attorney General`s Office has also asked the Public Ministry to investigate the cause of the fire at the home.Morfín said her office "has the duty to protect and represent children and adolescent and those vulnerable and that lack representation."Morfín also said her office would open an investigation into the cause of the fire.She said they had been trying to reduce the number of teenagers and children at the home from 720 around September and October of last year to around 580."We cannot recover those lives but we can analyze the system, make it transparent," Secretary of Welfare Carlos Rodas said."That it is not about egos, it is not about personalities," he added. "These are boys and girls, teenagers."Rodas said his office will pay for the funeral services.Source: CNN