Some of the evidence led investigators to believe a "criminal act" may have contributed to the train crash, Forget said Tuesday.
But Forget said authorities would lay no blame until the investigation shows exactly what happened.
All businesses and factories in the affected region that are able were reopening Wednesday morning, Roy-Laroche said. She said the Red Cross would begin distributing vouchers to those returning home for food and other essential items, with the funds for the vouchers donated by people in the community and businesses in the region.
The mayor urged tourists not to cancel their reservations in the area, noting that some 300,000 people visit the region between May and October every year. And she thanked people from around the world who sent messages in the aftermath of the tragedy.
"All these messages give us the strength to face this catastrophe," she said.
Quebec Premier Pauline Marois said the provincial government would provide $25 million in emergency assistance immediately, with another $25 million to help with reconstruction efforts.
"It's small comfort, we know," Marois said. But she said the government hopes rebuilding will become "a mobilizing force" for the town.
Tuesday, some 1,200 residents were allowed to return to their homes in the area. Among them was Michel Gagnon, who was eating lunch Wednesday on his patio, a few blocks from the edge of the cordon.
Gagnon said Lac-Megantic's downtown had lost everything, but within a few years, "everything will be back up."