Honduran President Porfirio Lobo pardoned a convicted murderer who helped save hundreds of his fellow inmates during last week’s deadly prison blaze that killed over 350 people.

Marco Antonio Bonilla, also known as Shorty, was outside of his cell when the fire broke out. After the guard holding the keys disappeared, Bonilla used another set of keys to open the doors of several barracks, each housing about 100 men.

Some witnesses said the guard responsible for the keys threw them on the ground, while others said Bonilla demanded the keys from the guard and started opening doors. Inmate José Enrique Guevara, who suffered burns, said Bonilla picked up a bench and broke the lock on his cell block, No. 6, where the fire started, and saved his life.

"He put himself at incredible risk trying to save lives during the tragedy," Lobo said during a televised meeting with ministers, according to the Associated Press.

Bonilla was not immediately available for comment, but the 50-year old prisoner who worked as a nurse in the jail, reportedly had just a few months left to serve of a murder sentence and was allowed to live apart from the other inmates.

Honduras Prison Fire Leaves Hundreds Dead

Honduran officials' explanation of what happened continued to change last week after the fire raced through five barracks of the Comayagua prison farm, burning and suffocated screaming men who were trapped behind locked doors. Witnesses said the guard with the keys was either scared by flames or refused to open the door.

There were six guards supervising 852 prisoners the night of the fire at the prison about 55 miles (90 kilometers) north of Honduras' capital, Tegucigalpa.

Honduran officials initially said the blaze broke out after an inmate threatened to burn the prison down, including in a cellphone call to Comayagua Gov. Paola Castro. The governor later retracted her story, saying she got only a phone message that there was a fire. She added that she had accidentally erased the message.

Many of the relatives of the inmates killed in the blaze have said they don't believe that the fire started in a single mattress or that it could have spread so quickly in a densely crowded cell, where dozens of inmates would have seen the fire and stomped it out.

"If somebody sets a mattress on fire, smoke starts coming out and the others put it out," said Marco Rivera, 32, a tire shop operator whose nephew, Eduardo Osmar Chaverria López, was one of the inmates presumed dead. "Many people (among the relatives) say gallon jugs of gasoline were found inside, and that it was premeditated."

On Tuesday investigators from the United States said that the fire was accidental, and may have been caused by a lit match, cigarette or some other open flame.

President Porfirio Lobo also announced he is pardoning a prisoner who helped free hundreds of inmates after the guard with the keys disappeared. In at least one case, a witness said the hero inmate picked up a bench and broke the lock on a cell.

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The U.S. Embassy in Honduras said in a statement that a team of investigators from the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives "was able to rule out other possible causes of the fire, such as a lightning strike, electrical causes, or the use of a flammable or combustible liquid."

The death toll from the Feb. 14 fire at the Comayagua prison rose to 360 Tuesday after another victim died in a Tegucigalpa hospital from his burns.

"The fire is believed to have begun in the area of the top two bunk beds in the fourth column along the western side of the prison's module six, which ignited nearby flammable materials," the statement said. "The cause of the fire is believed to have been an open flame (the source of which could include, but is not limited to, a cigarette, a lighter, matches, etc.), although the actual ignition source was not recovered."

It didn't identify the inmates in those bunks.

The statement called the cause of the fire accidental. There were 105 prisoners crammed into rows of bunks four levels high in the barracks where the fire started. Only four survived.

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The statement did not say why the investigative team concluded the fire was set accidentally after Honduran officials first said last week that it was ignited by an angry inmate who had threatened to torch the prison and later that it was caused by inmates who were fighting over a mattress.

The ATF referred all comment to the U.S. Embassy.

"No information gathered during the course of the investigation, including from witness statements, led ATF investigators to believe the fire resulted from anything but accidental causes," embassy spokeswoman Lisa Venbrux said in an e-mail.

The ATF statement said it found no evidence of any fuel. It said crowding, poor safety practice and the presence of flammable materials in and around the tightly packed bunk beds caused the rapid spread of the flames. Inmates had clothes, curtains and small electrical devices hung from their bunks. Some also had materials to light makeshift kitchen stoves, according to some of the survivors.

The inmates were crowded into two long racks of bunks, the beds stacked four high and stretching the length of the room narrow room. The two bed structures were separated by an aisle barely a yard (meter) wide.

Officials initially put the fire's toll at 355 deaths, but five inmates have since died, raising the total to 360. The latest was Juan Angel Arias, 66, who died Tuesday as a result of his burns, said Dr. Manuel Boquin at Hospital Escuela in Tegucigalpa.

A government report this month said the prison's capacity was 500, and more than half of the 852 inmates crowded inside were awaiting trial. Some had yet to be charged.

Based on reporting by The Associated Press.

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