(CNN) -- Tank cars filled with crude oil continue to burn and the death toll is expected to rise 36 hours after a runaway train exploded in a small Canadian town, local police said Sunday.
At least five people were killed and around 40 people are listed as missing in the tiny lakeside town of Lac-Megantic, Quebec, local police spokesman Lt. Michel Brunet said in a news conference. The bodies are heavily burned and have been sent to Montreal for identification. Brunet said "we know that there will be many more" deaths.
Firefighters are still working to extinguish two burning tank cars that are at risk of exploding, said Lac-Megantic Fire Chief Denis Lauzon. Firefighters have to stay 500 feet away from the tankers still on fire.
The train, pulling more than 70 tankers of crude oil, had been parked for the night 7 miles away from Lac-Megantic, according to a statement from the Montreal, Maine & Atlantic Railway. It slipped downhill, derailed, then crashed into downtown, leveling dozens of homes and buildings. Tankers exploded, sending thick plumes of smoke into the night sky.
Witnesses told the CBC they heard five or six explosions.
One witness saw the first train tanker tip over and yelled "run, run!" as he dashed toward the lake of the same name as the town. He told CBC the flames chased him to the edge of the water.
"The fire was moving so quickly," he said. "We saw balls of fire shooting out onto the water."
One woman told CNN affiliate CTV she was working at a bar nearby and got off work an hour before the accident.
"I have no news from my friends, I haven't heard from any of them," she told tearfully told CTV. "I can't say more than that. We're waiting for confirmation."
Investigators only have access to a small part of the scene, said Quebec provincial police spokesman Benoit Richard. They aren't ruling out foul play at this point, Richard said.
Amid the chaos, friends and families are scrambling to find their loved ones.
More than 17,000 people have joined a Facebook page to help people connect with their loved ones in the town. Locals and outsiders have posted desperate notes to try to figure out where their friends and family were on the night of the crash.
Some posts bring relief -- "Mom it is alisun and oceannie and rosaly we are all alive I love you," one reads in French.
Others look less promising.
Multiple posts ask about Guy Bolduc, a singer who was performing at Musi-Cafe in town.
"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.
The group administrators ask that members not post about deaths until they're confirmed.
Residents told the CBC they have never seen anything like it.
"It's dreadful," Claude Bedard said. "It's terrible. The Metro store, Dollarama, everything that was there is gone."
The train's engineer stopped for the night and "tied down" the train 7 miles away from the town before he checked into a motel Saturday night, the company statement said. The train had stopped for a crew change.
"Railway personnel were able to pull 13 carloads intact from the site at the rear of the train," the statement said. "We extend heartfelt condolences to those residents of Lac-Megantic who have lost their homes and businesses, and particularly those who have suffered injuries and lost loved ones."
Mayor Colette Roy-Laroche said at a news conference that she hasn't spoken to the railway company.
"It's an incredible loss to our community," Roy-Laroche said about the number still missing.
Authorities evacuated more than a third of the town of 6,000 people, most from the center of the town and a home for the elderly.
As authorities worked to get more details, residents of the scenic town grappled with the loss.
"It's like the town has been cut by a knife," Sgt. Gregory Gomez del Prado told the CBC.
Resident Amanda Gabrielle said the train crashed on her birthday. She lost her dog, she's now homeless, and she doesn't have any family or friends.
"I lost everything," Gabrielle told the CBC. "I don't know what's going to happen to me."
Emergency services were working overnight to deal with the crisis.
"We have deployed all resources to ensure that we can support our citizens," Roy-Laroche said.
Firefighters from the United States are helping to fight the blaze. Five trucks deployed from Franklin County, Maine.
For information on missing people, call 1-800-659-4264.