The co-owner of a supermarket and five others were charged with manslaughter for a fire that killed 464 people, after a security guard testified he was ordered to lock the burning store's doors to prevent looting, trapping shoppers inside.

Owner Juan Pio Paiva rejected the allegations as he was brought to jail Tuesday, shouting, "My conscience is clear."

Meanwhile, desperate relatives searched for family members missing since the fire Sunday, but the destruction and the intensity of the blaze made it likely that some bodies would never be found. Maria Ines Florentin, despondent at not being able to find her 19-year-old sister Angelica, cried out for help.

"Please, if you have any clues to my sister, I am desperate," she said. "I've been to the hospitals, to the morgue and she's not on any list and I can't find her anywhere."

Interior Minister Orlando Fiorott said Wednesday early evidence pointed to an accidental gas leak as the cause of the fire. He said there were no signs of sabotage or that the blaze had been intentionally set.

"The investigations clearly point toward a gas leak and the rapid combustion of the merchandise," said Fiorotto, cautioning that findings were only preliminary.

Officials have said they were checking reports an exploding gas canister could have started the flames that forced one floor to collapse, crushing cars and burning many bodies beyond recognition.

With the wreck of the supermarket still reeking of smoke, Paiva, a business associate, and four security guards were charged with involuntary manslaughter, Channel 13 television reported Tuesday night. Paiva's son was still under investigation.

The charges came after chief investigator Edgar Sanchez said a security guard testified that he was told via radio to lock the doors when the fire began. Sanchez said the guard didn't know who gave the order. "He couldn't identify the voice that spoke to him over the radio," Sanchez said.

Judicial officials had no immediate comment on the report, which come on the heels of an exhortation by President Nicanor Duarte (search) for a swift and thorough investigation into the tragedy at the Ycua Bolanos (search) supermarket, food court and parking garage in suburban Asuncion, capital of Paraguay (search).

Earlier Tuesday, authorities said the toll soared to 464 dead, while 409 people remained hospitalized with burns and other injuries.

So many funeral marches were held that mourners waited turns outside cemeteries around the capital and florists ran out of roses and carnations. Burials, including some for infants in tiny caskets, followed back to back.

More workers were called in to help dig graves and local reports said some mourners were asked to bury their dead outside the capital.

"We're just overwhelmed," said one cemetery worker who identified himself only as Raul. "Nothing like this has ever happened and we just weren't prepared for this."

Rifle-toting troops stood guard at the rose-colored supermarket, cordoned by a yellow police tape and still reeking of smoke as investigators examined the scene.

Dozens of family members wandered desperately between hospitals and morgues where they looked over badly burned bodies. Others held up photographs, hoping rescue workers might recognize them.

Dozens of volunteer psychologists circulated among the crowd hoping to console relatives, and forensic experts urged some of them to bring dental records and X-rays to help identify victims.

"I'm looking for my mother! Where is she?" shouted a sobbing Carlos Montiel. Unable to identify her among the bodies, he frantically yelled a description of her: "She's tall, brown, and has black hair."