BY DEBORA REY
Associated Press

ASUNCION, Paraguay - The death toll from a supermarket blaze soared by more than 100 to reach 464 Tuesday, as a security guard told investigators he was ordered to lock the building's doors to prevent theft just after the fire began.

Dozens of families were still searching for lost loved ones as prosecutors filed murder charges against the store's owners and security guards over reports that doors were locked, trapping shoppers inside during Sunday's fire, the worst disaster in decades in this impoverished South American country.

The attorney general's office put the death toll at 464, saying 325 bodies had been identified and 139 others still had not. Officials also said 409 people remained hospitalized.

The blaze broke out during lunch hour at the three-story supermarket in a suburb of Asunción, the capital. Flames quickly spread through the Ycua Bolanos supermarket, food court and parking garage, causing a floor to collapse. Officials say they are checking reports that an exploding gas canister could have started the flames.

Prosecutor Edgar Sánchez, who is leading the investigation, said a security guard told authorities that at the outset of the fire he received orders over a radio to lock the doors to prevent theft.

Sánchez said the guard ''didn't know'' who gave the order. ''He couldn't identify the voice that spoke to him over the radio,'' the prosecutor said.

The store's two owners and four security guards who were on duty at the time of the fire were charged with criminal homicide. If convicted, they could face up to 25 years in prison. Judicial authorities also said they also ordered a freeze on the assets of Juan Pio Paiva, who owns the supermarket with his son, Daniel.

A store manager, Fernando Humberto Casaccia, was also charged with criminal negligence for allegedly refusing to help people escape from the burning building.

Pio Paiva dismissed speculation that the doors had been deliberately locked to prevent looting and said the building met safety codes.

As funerals and burials were held across the capital, the mood remained edgy. Authorities evacuated a second Asunción supermarket Tuesday after reports of a gas leak.

At the site of the fire, firefighters and others continued searching for victims in the rose-colored building, which was cordoned off by yellow police tape and guarded by rifle-toting soldiers.

Nearby, some families were trying to locate the bodies of relatives missing and believed dead. Dozens of family members gathered to look over badly burned bodies. Others held up photographs, hoping rescue workers might recognize them.

''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.

One woman, Blanca Valinotti, said she believed her 25-year-old daughter Nidia had died in the blaze but had not seen her name on a list of victims circulated by authorities.

''I've given up all hope,'' she said. ``I know she's dead but at least I want to find the body. I need to know what happened to her.''