Skirmishes have broken out between security forces and relatives seeking news of inmates after more than 350 people reportedly died during a prison fire described as the worst disaster of its kind in Latin America in at least 25 years.
The fire broke out at the Penitenciaria Nacional de Comayagua in Honduras at about 10.50pm on Tuesday, destroying half of the 400-capacity prison that had been housing some 850 prisoners.
In a televised address the Honduran president, Porfirio Lobo Sosa, expressed "his deepest sympathies for the families that today cry."
"My heart is with you," he said after an emergency cabinet meeting on Wednesday morning.
Authorities urged calm as clashes broke out between prison guards and family members trying to gain access to the prison, in the town of Comayagua, about 50 miles north of the capital, Tegucigalpa.
Television images appeared to show guards firing rubber bullets and tear gas to disperse angry crowds who had gathered at the prison's gates to demand information about the whereabouts of their relatives.
"We understand the pain of these relatives but we must follow the proper legal proceedings," the security minister, Pompeyo Bonilla, told reporters. "We are calling for calm. This is a very difficult situation."
Throughout the day, the official death toll from the blaze steadily rose from dozens to well over 300. By mid-afternoon authorities admitted that at least 375 prisoners had probably died. About 475 prisoners were thought to have escaped while a preliminary list of survivors released by authorities contained 146 names.
"Honduras is in mourning," Bonilla told reporters during a visit to the jail in the early hours of Wednesday morning.
Speaking on local radio, Lucy Marder, the chief forensic science officer for the prosecutor's office, said 356 people out of 852 on the prison roster were unaccounted for and it would take days to identify all of the victims.
Colonel Leonel Silva, head of the local fire brigade, told the daily paper la Prensa there were numerous dead but refused to confirm a number. At least two prisoners were being treated for severe burns in Tegucigalpa, according to local reports.
La Prensa said firefighters were only able to gain access to the prison at 11.30pm, by which time many prisoners were already dead. Witnesses said they had seen bodies piled up in several cells belonging to prisoners who had apparently suffocated by toxic fumes.
Josué García, a spokesperson for the fire department, described the scenes inside the jail as "Dantesque" and said it would take time to identify all the bodies.
"About 100 prisoners were burned or suffocated by the gases created by the fire inside their cells, which were secured with padlocks. Unfortunately we could not get them out because we didn't have the keys to hand and couldn't find the guard who was carrying them," he told the Associated Press.
"When the fire started we called out to the people with the keys but they didn't want to open [our cells]," one prisoner, Rubén García, told el Heraldo newspaper.
On Wednesday morning, prisoners' relatives were reportedly crowding around the jail seeking news of their loved ones. Television images pictured weeping women and children, clutching mobile phones as they crushed up against the prison's perimeter fence.
"My brother was in unit six," one woman, Glenda Mejía, told AFP. "They have told me that everyone in [unit] six is dead."
"They have told me nothing," Carlos Ramírez, whose brother was in the prison, said.
The prison housed people convicted of serious crimes such as murder and armed robbery, Danilo Orellana, director of the national prison system, told the Associated Press.
There were conflicting reports about what had caused the fire, but survivors claimed an inmate had set fire to his bedding.
"Some of his cellmates said that he screamed: 'We will all die here!' And in five minutes everything burned," Orellana said. He did not identify the man or speculate about his motivation.
He denied there had been a rebellion. "This was not a riot. Several units caught fire and we are investigating the causes," he told la Prensa.
Silva, the fire chief, said the rescue effort had been delayed because of the sound of gunfire coming from within the prison.
As forensic officers struggled to piece together what had happened and Chile's president, Sebastián Piñera, agreed to dispatch forensic officers from his country to help identify the victims, Honduran media focused on the bleak conditions in the country's 24 prisons.
According to one report in la Prensa, the jails have capacity for about 8,000 prisoners but hold some 13,000.
Germán Enamorado, a Honduran human rights prosecutor, said he would investigate claims prison guards had opened fire on inmates after the fire broke out.
"We need to confirm if there was shooting and if it was directing at the prisoners or was simply preventative," he told el Heraldo.
Recent years have seen Honduras become a hub for drug smugglers moving cocaine into the US from South America and many studies now show Honduras has the world's highest murder rate. In 2010, there were about 82 murders per 100,000 inhabitants, according to the United Nations office on drugs and crime.