Medolla, Italy (CNN) -- The death toll from a 5.8-magnitude earthquake in northern Italy rose to 17 after the discovery of another body, officials said Wednesday, as questions were asked about why factory buildings collapsed.
The latest body was found in the rubble of the collapsed factory in the area of Medolla, Italy's civil protection agency said.
The prosecutor's office in the province of Modena, where the quake was centered, opened an investigation Wednesday into the cause of death of the quake victims, many of whom were factory workers.
Investigators will examine how the factories were built and why they couldn't withstand an earthquake of Tuesday's magnitude.
Modena's chief prosecutor, Vito Zincani, told CNN that as modern buildings, they should have remained standing.
Most of the modern structures in the area were not damaged, he said, so the fact that some factories collapsed "shows an anomaly that needs investigation."
Look at high-resolution images of the disaster
The earthquake, which forced thousands of people from their homes, came nine days after a 6.0-magnitude quake struck the same region, killing seven people.
Tuesday's quake, which struck at about 9 a .m. local when many people had begun work, was followed by dozens of aftershocks. The U.S. Geological Survey recorded one of 5.6 magnitude.
Italian ministers met Wednesday morning and decided on several measures to be taken in the aftermath of the quake.
The government declared a state of emergency in the quake area and set June 4 as a national day of mourning, according to a press statement. An extra two-cent tax will also be added to gasoline to help finance the recovery effort, it said.
Italy's President Giorgio Napolitano, Prime Minister Mario Monti and the speakers of both Italian houses of parliament on the earthquake met later Wednesday at the presidential palace in Rome to discuss the disaster.
The towns of Mirandola and Cavezzo, northwest of the city of Bologna, were closest to the epicenter, civil protection authorities said.
Witnesses reported on Twitter that Cavezzo was about 70% destroyed. Pictures purportedly from the town, as well as a video stream from Italian newspaper Corriere della Sera, show damaged and destroyed buildings.
Churches and historic structures were among the affected buildings.
In the small town of Novi di Modena, a 65-year-old priest died inside his church as he tried to save its statue of the Madonna.
Construction workers who were out surveying the damage in Medolla were emotional as they spoke of their experiences a day earlier.
Mohmammed Mouhalhal told CNN he was at work when the earthquake struck. He and his fellow construction workers now fear for their jobs and their safety, he said.
He said no one could sleep Tuesday night and they stayed outside for fear of further quakes.
Some 50 tremors were felt in the area overnight.
Italian authorities are still assessing the economic impact of the earthquakes on the region, which lies in northern Italy, the heartland of the country's manufacturing industry.
Leaders of agricultural and industrial organizations, speaking to Italian media, have estimated the cost of the disaster at nearly one billion euros.
The Italian daily newspaper Repubblica puts the damage to the biomedical industry in Medolla alone at about €600 million ($751 million).
Many cheese makers are also among those affected.
Stefano Berni, president of the consortium that makes Grana Padano, a hard cheese similar to Parmesan, told CNN that some 350,000 whole cheeses, each weighing 40 kilograms (88 pounds), had been shaken to the ground. No more than 40% of those are likely to be salvageable, he said, leading to estimated losses of €70 million ($88 million).
About 600 cheese producers located in the area north of the earthquake epicenter have suffered damage to their production centers and warehouses, he said. About 50,000 families, including the milk producers and cheese makers, work for the industry.
Other factories and warehouses that have not been damaged by the quake will still suffer losses because they have had to halt production for safety checks.
Geophysicist Antonio Piersanti, of the National Institute of Geophysics and Vulcanology, told Corriere della Sera that it was possible more earthquakes could follow in the coming weeks.
The last significant earthquake in this area was in 1571. It was followed by about four years of aftershocks.
CNN's Hada Messia and Ayesha Durgahee contributed to this report.