Lac-Megantic, Quebec (CNN) -- Edward Burkhardt said he tried to get the people of Lac-Megantic, Quebec, to hear him, to try to understand that he had traveled to their town because he genuinely cared, he told CNN in an exclusive interview Thursday.
The 74-year-old chairman of Montreal, Maine & Atlantic Railway wanted to answer any questions from officials and hear people out about the anguish they feel after a driverless train carrying tank cars oil rolled out of control, exploding in an inferno that killed at least 20 people.
At least 30 more are still missing, most them probably dead, Quebec Provincial Police Capt. Michel Forget has said. The blaze may have vaporized victims, authorities said.
Burkhardt expected that he'd face raw emotions, but was surprised that so much anger was directed at him.
"I'd been told about it. I'd been warned about it," he said. "But it was worse than I thought. I thought people would respond to my willingness to come there. I mean, they were screaming about how I took three days to get there."
The tragedy occurred Saturday. Burkhardt arrived in Lac-Megantic Wednesday.
"Well, the three days we had a dozen people on the scene and I was organizing all kinds of things that were necessary," he said. "And I figured I didn't really need to be in the way of people there when they were trying to put the fire out and that sort of stuff.
"I would wait till the dust settled to a certain degree and then I would come. That's what I did, but this was not well-received at all."
On Wednesday, two middle-aged men shouted at Burkhardt as he spoke with reporters, calling him an obscene name and challenging him to walk into the heart of the tragedy.
One of the men, Pierre L'Heureux, told CNN he knew at least half the people who were dead or missing.
"They should put that guy in prison," L'Heureux said. "He's a murderer ... he should be in prison."
"People wanted to throw stones at me. I showed up and they threw stones. But that doesn't accomplish anything," Burkhardt told CNN said.
Attempts to set up meetings with city officials and rescue workers were unsuccessful, he said.
"I failed with all that," he told CNN. "They were too busy. They didn't want to meet."
His visit to the town was "designed to get a healing process under way," he said, but he was misunderstood.
"Maybe I didn't present my case very well. But I'm not a communications professional. I'm a manager."
The executive with more than 50 years in the railway business told CNN that he could get "quite emotional" talking about the train disaster.
"They talked about that I had no empathy, or no sympathy, and in fact I have plenty," he said. "I can imagine myself being in that kind of situation and I also would be grieving and I'd be very unhappy. I'd be very mad about the whole thing so I certainly understand the need to vent. But it comes a point where it's totally unproductive."
Burkhardt told CNN that that is why he has decided not to return to Lac-Megantic Thursday. CNN spoke to him in Sherbrooke, an hour and a half outside Lac-Megantic, the closest area with an available hotel room.
"I'm willing to come back (to Lac-Megantic) at a later date when maybe things are a little calmer, a little more settled down," he said.
CNN asked the railway executive what he believed was the cause of the disaster.
"Well, there's no question that it's a brake failure on the train. The train rolled away. That speaks for itself, doesn't it?" he answered. "There's no sugarcoating that."
"What caused the brake failure is a bit complex it's more than one factor," he continued, saying that the company is still "trying to pull all the pieces together on that."
Burkhardt has said that the train engineer reported to railroad managers that he set 11 hand brakes on the train cars before they broke away from their engines. On Wednesday, the executive said he felt "it's questionable" whether the engineer indeed did that.
"Our general feeling is now that is not true," Burkhardt said Wednesday, adding that the engineer had worked for the MM&A for "many years" and "had a completely clear safety record up until Saturday."
On Thursday the railway executive told CNN that the engineer is suspended, and Burkhardt has not spoken to him.
"The investigation is continuing, but if we decide to bring internal charges against the engineer he's entitled to a full and impartial investigation with his union at his side," Burkhardt said. "We're -- he's got a big problem on his hands and we're not trying to make that worse for him personally."
CNN's Anna Coren and Adam Reiss reported near Lac-Megantic. Ashley Fantz wrote this article in Atlanta.