CANADA (CNN) — The chairman of the company whose driverless train barreled into the small Quebec town of Lac-Magantic and unleashed a deadly inferno told a Montreal newspaper he believes it had been tampered with.
"We have evidence of this," Ed Burkhardt said in an interview published by the Montreal Gazette. "But this is an item that needs further investigation. We need to talk to some people we believe to have knowledge of this."
The company did not immediately return phone calls from CNN about the report.
Burkhardt is the chief executive officer and president of Rail World, the parent company of the Montreal, Maine & Atlantic Railway, the operator of the derailed train.
Seventy-two tanker cars carrying crude oil jumped the track early Saturday, setting off a huge fireball.
At least 13 people are dead and 37 are missing.
Officials in the town 130 miles east of Montreal say some were likely vaporized by the sheer intensity of the blaze, which burned for 36 hours.
The paper says Burkhardt doesn't "believe that the event was malicious or an act of terrorism."
Burkhardt is quoted as saying that his company has begun an internal inquiry that has been "limited by rescue efforts and parallel investigations under way since Saturday."
"There are a number of missing pieces here -- but we'd like to have a complete idea about the cause," Burkhardt is quoted as saying. "We are prepared to go in and do this very quickly, as soon as we can gain access to people and to the site."
The train had already been on fire hours earlier before the accident, Canadian broadcaster CBC reported, sourcing fire officials.
Firefighters in the town of Nantes, a few miles away extinguished a small blaze on the freight train.
When they left, it was still parked there, where it was supposed to stay for the night, the company responsible for the train said.
Air brakes holding it in place likely failed, allowing the train to barrel downhill into Lac-Megantic, the Montreal, Maine & Atlantic Railway said.
Investigators plan to check the brakes, once the crumpled, burned out tankers are accessible.
The train had picked up speed before rolling into the town not far from the U.S. state of Maine.
"Usually they're traveling between 5 and 10 miles an hour," said Quebec police officer Benoit Richard. "On that night, this train was going at least between 30 and 40 miles an hour."
Sonia Pepin heard the train like never before that night.
The tracks are just a few feet from her home.
The whole house shook, she said.
Investigators with the Transportation Safety Board of Canada found the locomotive event recorder, which they can analyze for information on throttle position and speed, among other data.
More and more petroleum products have been gliding over rails in tanker cars in the last five years, according to the railroad industry.
And every month since April some of them have derailed.
Good fortune may have prevented the Lac Megantic disaster from occurring sooner.
Last month, four Canadian Pacific rail cars carrying flammable petrochemicals used to dilute oil derailed on a flood-damaged bridge spanning Calgary's Bow River, according to the Calgary Herald.
In another incident involving Canadian Pacific, five tankers containing oil derailed in rural Saskatchewan in May, spilling 575 barrels of crude, the Toronto Sun reported.
A month earlier, 22 Canadian Pacific rail cars jumped the tracks near White River, Ontario.
Two of the cars leaked about 400 barrels -- almost 17,000 gallons -- of oil, The Globe and Mail in Toronto reported.
Canadian Pacific was also involved in a stateside spill in March.
Fourteen cars on a milelong, 94-car train derailed in western Minnesota, about 150 miles northwest of Minneapolis, spilling about 30,000 gallons of crude, Reuters reported.
The runaway train that was a proven fire hazard rumbled toward the town of Lac-Megantic while patrons at the Musi-Cafe were enjoying a summer night.
They were sitting on the pub's front porch on Saturday.
When 1,500 residents who evacuated from the Canadian town return Tuesday, they will find its center gutted for blocks as if it had been bombed.
The Musi-Cafe is no longer standing.
Some of its patrons have been counted among the 13 confirmed dead.
"We know that there will be many more," said police Lt. Michel Brunet.
Authorities believe some of those still missing were in the pub at the time of the accident.
The night the Musi-Cafe disappeared in flames, Quebecois musician Guy Bolduc had been giving a concert there.
The pub's Facebook page is still standing and is filling up with messages of condolence, as has a page created for the victims of the disaster.
Bolduc's fans are searching for him on social media.
"All of his fans, all over Quebec, but also his fellow singers (of whom I am one) hope to see him again alive!!! Come on my GuyBol, come out of your hiding place," one member wrote.
They fear the concert may have been his last.
"Hot zones" lingering more than two days after the train derailment were hampering authorities' efforts to continue their search for missing people.
Forensic specialists have asked victims' families for hair samples, clothing, anything to help identify their loved ones.
In a town of just 6,000 residents, most everyone is affected by the deaths -- and by the loss of homes.
Prime Minister Stephen Harper has described the scene as a "war zone."