Vanessa Gera, ?Frances D’Emilio and Hakan Kaplan

AMATRICE, Italy: Italian authorities are vowing to investigate whether negligence or fraud in adhering to building codes played a role in the high death toll in last week’s earthquake in Italy.

They also called for efforts to ensure organized crime doesn’t infiltrate lucrative construction contracts to eventually rebuild much of the picturesque towns leveled in the disaster.

Meanwhile, rescue workers pressed on with the task of recovering bodies from the rubble, with hopes of finding any more survivors virtually vanished more than four full days after the powerful quake.

Over the past two days, they found six more bodies in the rubble of Hotel Roma in Amatrice, the medieval hill town in mountainous central Italy that bore the brunt of destruction and loss of life in the powerful quake. They recovered three and by late Sunday were still working to retrieve others that were hard to reach.

It wasn’t clear if those six were included in the overall 290 death toll given by authorities. The Civil Protection agency, which combines the figures it receives from different provinces affected by the quake, said the number is lower than the previous toll of 291 dead due to a correction in the numbers from the province of Rieti, where most of the victims died.

The quake that struck before dawn Wednesday also injured nearly 400 people as it flattened three medieval towns near the rugged Apennines. Prosecutor Giuseppe Saieva, based in the nearby provincial capital of Rieti, said the high human death toll “cannot only be considered the work of fate.”

“The fault lines tragically did their work and this is called destiny, but if the buildings had been built like in Japan they would not have collapsed,” Saieva said in comments carried by Italian media.

Investigations are focusing on a number of structures, including an elementary school in Amatrice that crumbled despite being renovated in 2012 to resist earthquakes at a cost of $785,000. Many were shocked that it didn’t withstand the 6.2 magnitude quake.

After an entire first-grade class and a teacher were killed in a 2002 quake in the southern town of San Giuliano di Puglia, Italian officials had pledged citizens that the safety of schools, hospitals and other critical public buildings would be guaranteed.

Questions also surround a bell tower in Accumoli that collapsed, killing a family of four sleeping in a neighboring house, including a baby of 8 months and a 7-year-old boy. That bell tower also had been recently restored with special funds allocated after Italy’s last major earthquake, which struck nearby L’Aquila in 2009.