In Paraguay, school is in session again after a three-day national mourning period following Sunday's horrific supermarket fire that killed more than 400 people. Authorities are still investigating the cause of the deadly fire.

Psychologists and priests were present at the reopening of Asuncion schools to help children cope with the devastating fire that left about 45 children dead.

Entire families perished together in the blaze. The bodies of some children were found still clutched in the arms of their parents.

Paraguay's president, Nicanor Duarte, visited the site for the second time this week, and confirmed reports that the building had been in violation of several construction codes.

He blamed bribery and corruption for the failure to build the structure with proper emergency exits and security systems.

Authorities say the majority of those killed in the blaze were employees of the supermarket.

Crews are still working to locate and identify charred remains. Doctors are relying on DNA and dental records to help determine victims' identities.

Hundreds of people are still hospitalized with severe burns. The American Red Cross has donated skin tissue for burn victims. Neighboring South American countries have sent medicine, personnel and supplies to Paraguay, one of the poorest countries on the continent.

Forensic experts have been analyzing the interior of the three-story building, to determine exactly what caused the fire. Officials have ruled out a terrorist attack, saying the inferno likely started from a gas leak.

Meanwhile, the supermarket's co-owner and four others remain in jail on charges that they locked the doors after the fire broke out to prevent looting.