Pascal Fillion, who lives near the seniors' home in L'Isle-Verte, said he ran outside to find a group of locals and firefighters already at the scene, trying everything to save the panicked people inside.
For the most part, he said, rescuers felt helpless against a fast-moving blaze with smoke so thick it was nearly impossible to approach the building.
"It was just like straw on fire," Fillion said in the waterfront town of 1,500 people in Quebec's Lower St. Lawrence region.
"People tried to do whatever they could, but the fire was so intense that there wasn't much that could be done...
"I saw people crying, I saw people collapse because they were watching those people burn."
Just six months after Canadians were rocked by the Lac-Megantic tragedy, another Quebec town found itself waiting to learn how many people it had lost after fire ripped through the Residence du Havre.
And just like in Lac-Megantic, the destruction struck shortly after midnight.
Grim-faced provincial police confirmed that five people were dead and another 30 missing after flames consumed part of the 52-unit home.
Fillion said he saw several rescuers drop to the ground after being overwhelmed by smoke during their frantic efforts to get terrified residents out of the building.
At least one attempt, he added, was made to climb a ladder to one man cornered on his third-floor balcony.
"He was crying out for help — he was screaming," Fillion said.
"I saw him fall to the ground. I saw that the fire had gotten him. He truly died in a horrible way. There was nothing that could be done."
Parts of the three-storey home, which opened in 1997, had sprinklers, while others didn't.
The local fire chief said sprinklers did go off, triggering the fire alarm and allowing firefighters to gain access to about one-third of the building.
Thursday's blaze erupted in the older section of the residence, which a Quebec Health Department document from last July states was constructed of wood.
The document also says the building had a fire alarm and that each room was equipped with a smoke detector.
After firefighters had finished taming the blaze, the home's hardest hit area had been reduced to a piece of facade, the fireproof elevator shaft and a mound of rubble that steamed for hours from the heat trapped inside.
The bitterly cold temperatures contrasted with the roaring flames that illuminated the night sky as firefighters poured gallons of water on the burning building.
As morning dawned, the burned section of the facility resembled a macabre ice palace. The structure was covered with huge icicles and sheets of ice, which firefighters said ranged from a few inches to as much as a foot thick.
Officials said the ice complicated the search for the missing.
Many of the residents were over 85 and all but a handful had limited movement, being confined to wheelchairs and walkers.
Fillion said the impact of the fire will affect just about everyone in L'Isle-Verte.
"For us, they were all people everyone knew," he said.
Deputy mayor Ginette Caron said only five residents in the 52-unit centre were fully mobile.
"The rest were semi-autonomous, practically no longer autonomous," Caron told a news conference. "Wheelchairs, walkers, people who can't move around. People with Alzheimer's, in the last stages of life."
At least three people were injured, although the extent of their injuries was unclear.
On Thursday afternoon, Quebec provincial police encouraged relatives of the residents to meet with them at a local school to help in their investigation. A local church was also opened for those who wanted to pray.
A stricken Jacques Berube stood outside the residence as he pondered the fate of his missing 99-year-old mother, Adrienne Dube.
Berube, 70, tried to locate her at a hospital in nearby Riviere-du-Loup as well as at a school in L'Isle-Verte, where residents were initially taken.
He was getting ready to hear the worst about his mother, who is blind but still mobile.
"I went near the building; the corner where her room was is burned," he said. "I'll just have to wait and see. I don't like it. But I don't have any choice. It's just reality."
Retired RCMP officer Pierre Filion, who had a cousin and an aunt living in the residence, said the tragedy had shaken the community.
"It's going to take a long time to start living normally," said Filion, whose missing relatives are both in their 70s.
"It's a very bad day for L'Isle-Verte. It's one of those days you should forget."
Mario Michaud, who lives across the street from the building, said he witnessed the drama unfold shortly after midnight.
"I got up to go to the toilet and I saw smoke," Michaud told local newspaper Info Dimanche.
"The fire had started on the second floor. I woke up my girlfriend and called 911. I saw the firefighters and they got to work.
"A woman on the second floor was shouting and she went out on to the balcony. Her son went to get a ladder but he couldn't get to her. She burned to death."
Provincial police Sgt. Ann Mathieu said the fact 30 people were missing didn't necessarily mean they were all dead.
"Some people may have gone elsewhere and there may have been people staying with family," Mathieu said.
She urged people who have any information on people considered missing to call police.
The residence also housed a social agency, a pharmacy and a hair salon.
Most residents were older than 75 and 37 were older than 85. The building included both single rooms and apartment-style dwellings.
Agnes Fraser's 82-year-old brother, Claude, was among the missing, but she said she knew she would never see him again because he lived in the section of the building destroyed by the flames.
"It's done," said Fraser, who added that her brother enjoyed living in the home.
"It was a very nice residence, it was very well maintained and there were some very good employees as well."
Therese Rioux, a volunteer at the local used-goods store, said she probably knows, or had at least crossed paths with, everyone who was unaccounted for.
"For the elderly, who wanted to finish their days in safety, and to die this way — it's terrible," said Rioux, who woke up in the middle of the night, saw the flames and called 911.
All she could do was watch helplessly from her window as fire consumed the building.
Several fire departments in the region were called in to help extinguish the blaze.
Firefighters were unable to carry out a complete evacuation of the residence because the intensity of the fire limited their access.
"It was a total fire," said L'Isle-Verte fire chief Yvan Charron. "A third of the building was still standing and that was evacuated 100 per cent, but the cold (definitely) complicated things."
Firefighters arrived within eight minutes of getting the alarm and a total of six municipalities sent crews to battle the blaze, which was in the centre of the community about 250 kilometres northeast of Quebec City.
Several nearby houses were also evacuated as a precaution.
The fire broke out in -20 C temperatures, causing equipment to freeze, Charron said.
Even hours after the fire had been brought under control, some places were still too hot or unstable to allow investigators to examine them.
"There were trucks that were frozen, pumps that were frozen, hoses, but we were able to thaw them out," he said.
The president of an association that represents Quebec seniors' residences, praised the Residence du Havre as a fine facility.
Yves Desjardins said he'd met owner Roch Bernier several times and described him as a good man who ran a popular and excellent residence.
"Mr. Bernier is in shock," said Desjardins, adding the owner spent the night at the scene.
"He's not only the owner, but he loved the residence and he was very close to those people."
Prime Minister Stephen Harper offered his sympathies in a statement.
"On behalf of the entire country, I offer my sincere condolences to the family and friends of those who passed away following the fire at a seniors' residence in eastern Quebec last night," Harper said.
"My thoughts and prayers are also with those who remain unaccounted for and all those who have been injured."
Quebec Premier Pauline Marois sent a message from Davos, Switzerland, where she was attending the World Economic Summit.
"I want to extend my condolences to all the families affected by this terrible fire," Marois said. "I have been in touch with my office and we are doing everything we can to support the community and families.
"It's a private centre but we're talking about human beings, so we'll do whatever we can. I am deeply saddened by this event."
Canada has experienced a number of similar tragic fires in recent years.
One in Hawkesbury, Ont., in May 2012 claimed the lives of two people, while one person died in a seniors' apartment building in London, Ont., last October.
A blaze in June 2009 at a retirement residence in Orillia, Ont., killed four people and left six elderly residents critically injured.
A coroner's inquest following the fire made 39 recommendations related to automatic sprinklers in retirement homes and assisted living centres.
That led to a new law in Ontario, which took effect on Jan. 1, requiring all retirement homes in the province to have automatic water sprinkler systems.
Elsewhere, a fire at a retirement home in Langley, B.C., in April 2012 left a man dead and sent several other residents to hospital. And a woman in her 70s died in a fire at an Edmonton seniors residence in August 2012.
In August 1980, 21 one people was killed and 35 were injured in a fast-moving nursing home fire in Mississauga, Ont. Authorities said most of the victims died of smoke inhalation and extreme heat in the facility, which housed 198 residents.
In December 1976, fire raced through a two-storey nursing home in Goulds, NL, killing 22 people, including a 105-year-old woman.
The wood frame building in the community just south of St. John's was home to as many as 30 elderly persons.
The Lac-Megantic disaster in July saw 47 people killed when an out-of-control train loaded with fuel derailed and exploded.
Fillion said he kept thinking about Lac-Megantic every time he tried to describe what he saw.
"For us, it's like Lac-Megantic ... it's a big catastrophe."
— With files from Alexandre Robillard in L'Isle-Verte and Peter Rakobowchuk and Sidhartha Banerjee in Montreal
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