About 1,500 of the 2,000 residents forced to leave their homes when the unmanned train hauling crude oil crashed and ignited a huge fire and series of explosions in Lac-Megantic, Quebec, Saturday may be allowed to return home Tuesday, the Canadian Broadcasting Corp. reported.
Families were being asked to provide DNA samples from their missing relatives to help identify the 13 bodies found so far, the network said.
Provincial police Sgt. Benoit Richard told The (Montreal) Gazette investigators were still searching for 37 bodies.
The newspaper said police investigators are finding more remains as firefighters allow them closer to the epicenter of the disaster, which destroyed 40 buildings in the town.
"I just want our citizens to know that we're doing everything we can to get them home as quickly as possible," Lac-Megantic Mayor Colette Roy-Laroche said Monday. "It might take a while, but we're trying to make sure that the area is as safe as possible."
A boil-water advisory was in effect as a precaution.
Environment Quebec was assessing the damage caused by the train crash, fire and explosions because of the possibility that hundreds of thousands of gallons of oil seeped into the soil and water, the Gazette reported.
"From what we've observed, the grounds in downtown Lac-Megantic vary," an Environment Quebec representative said. "Some parts of town are covered in a black substance, like a soot. Others appear to be covered in something that resembles oil."
Environment Canada said the extent of the environmental damage to the nearby Chaudiere River wasn't known.
The multiple blasts Saturday occurred over several hours and rocked the community of 6,000 residents, about 155 miles east of Montreal.
City Hall was off limits because of dangerous conditions.
Canadian Prime Minister Stephen Harper characterized the downtown as a "war zone" Sunday after touring the devastation.
Harper said the federal Transportation Safety Board and police were investigating.
Montreal, Maine & Atlantic Railway, which sent representatives to the city, said a locomotive shutdown may have released the air brakes that were supposed to hold the 73-car train stationary overnight.