Media playback is unsupported on your device Media caption Lac-Megantic resident Adrien Aubert filmed the aftermath of the blast

A train operator's boss has blamed a local engineer for a runaway train that derailed and exploded in a Quebec town, killing at least 20 people.

Rail World head Edward Burkhardt said he did not believe the last engineer had set a series of hand brakes, despite his protestations.

Residents heckled Mr Burkhardt as he visited the town of Lac-Megantic.

At least 30 other people are missing since Saturday morning's disaster and are "most probably dead", police say.

They say that one of the 20 recovered bodies has been identified and the victim's family has been notified.

No official list of missing people has been released, but unofficial accounts have been circulating on social media.

At least 30 buildings were razed by the fireball from the explosion.

Railroad record

Making his first visit to the town on Wednesday, Mr Burkhardt said an engineer, who was in charge of driving the train, had been suspended without pay.

Media playback is unsupported on your device Media caption Rail World boss Ed Burkhardt: "It is very questionable whether the hand brakes were properly applied. In fact I'll say they weren't".

"I think he did something wrong," Mr Burkhardt said, flanked by police escorts, in Lac-Megantic.

At the scene Ed Burkhardt was no doubt speaking figuratively when he said he would have to wear a bulletproof vest in Lac-Megantic. Yet judging by his reception and the tone of the questions put to him, such concerns may have been relevant. His candid admission that the train's engineer may have been to blame may have won him kudos with some, but for others it only adds to the growing mistrust of freight train companies. Opponents point out that not only are there more trains carrying potentially hazardous cargo, but the trains are getting longer - the one that exploded into a fireball was made up of more than 70 pressurised oil containers. Hotel receptionist Charlotte Selby told me she would like to see an end to the oil trains all together. Her 16-year-old daughter Karyne phoned early on Saturday morning and told her: "Mum, Lac-Megantic doesn't exist anymore."

"It's hard to explain why someone didn't do something. We think he applied some hand brakes but the question is: did he apply enough of them?

"He said he applied 11 hand brakes. We think that's not true. Initially we believed him but now we don't."

The railway chief said he had not visited the Quebec town before Wednesday because he was dealing with the crisis in his Chicago office, where he said he was better able to communicate with insurers and authorities.

Earlier on Wednesday, Quebec Premier Pauline Marois said the company's response to the crash had been lacking.

"We have realised there are serious gaps from the railway company from not having been there and not communicating with the public," Ms Marois said as she announced a 60m Canadian dollar (£38m, $57m) fund to help victims and to rebuild the town.

The accident has also shone a spotlight on the railway's safety record. Over the past decade, the firm has recorded a higher accident rate than the rest of the US rail fleet, according to data from the Federal Railroad Administration.

In the last year, the railroad had 36.1 accidents per million miles travelled, in comparison to a national average of 14.6 accidents.

'Risky environment'

Some 200 officers were still searching the disaster site on Wednesday morning, and the heart of the town was being treated as a crime scene, cordoned off by police tape.

At the centre of the destruction was the Musi-Cafe, a popular bar that was filled at the time of the explosion.

But police said the effort was taking a toll on some crew members and two people had to be taken off the operation over worries for their physical condition.

"This is a very risky environment," said Quebec Provincial Police Sgt Benoit Richard.

On Tuesday, Quebec Police Inspector Michel Forget said investigators had ruled out terrorism as a cause of the disaster, but criminal negligence remained under consideration.

"This is an enormous task ahead of us," he said. "We're not at the stage of arrests."

Authorities have asked the relatives of those still missing to provide DNA samples by bringing in toothbrushes, razors and other items.

But the authorities have also warned some of the bodies may have been burnt to ashes in the explosion.

About 800 people were still barred from their homes as of Tuesday, and returning residents were asked to boil tap water before using it.

'Partial responsibility'

The train, carrying 72 cars of crude oil, was parked shortly before midnight on Friday in the town of Nantes about seven miles (11km) away.

Local firefighters were later called to put out a fire on the train.

While tackling that blaze, they shut down a locomotive that had apparently been left running to keep the brakes engaged.

Shortly afterwards the train began moving downhill in an 18-minute journey, gathering speed until it derailed in Lac-Megantic and exploded.

The fire department and the train's owners have appeared in recent days to point the finger at one another over the disaster.

Mr Burkhardt suggested on Tuesday evening that firefighters shared some of the blame.

"We don't have total responsibility, but we have partial responsibility," he told reporters in Montreal.

The train was carrying oil from the Bakken oil region in the US state of North Dakota to a refinery on the east coast of Canada.