A massive robotic arm was unable to reach an unstable escalator through the hole in the roof in order to push it aside and allow rescue crews to enter the Algo Centre mall in Elliot Lake, officials said Tuesday night.
The machine is now methodically plucking pieces of the mall's facade and some of the debris inside in order to clear a path.
"It's kind of like when you're reaching your arm in the cupboard and you have to move all the cups away to get to the one in the back," said Dan Heskey, the province's community safety commissioner. "It's a very surgical removal of certain pieces so that we can then get in and move (the escalator), as was the plan."
Meanwhile, workers from a Toronto rescue team are on standby, waiting for the precarious structure to be stable enough for them to go in.
The controlled demolition is part of a renewed bid to rescue any survivors.
While some residents cheered, others expressed concern that tearing chunks from the building might jeopardize the safety of anyone clinging to life within the rubble.
"It's heart-breaking, just knowing the instability of the building, that it might be causing more destruction on the inside," said Penny Craig, 39.
"It's horrifying to think what the people who may still be alive might be going through."
Fern Dumas, 70, echoed those concerns.
"If one of these slabs falls down that could be the end of somebody who's already been suffering for three, four days," said Dumas.
"And that eliminates the chance of them saving anybody."
The colossal yellow machine, which has a reach of 45 metres and took three trucks to transport from Toronto, rolled up to the mall earlier Tuesday along a road that was paved especially for it.
Once the delicate structures within are pushed out of the way, engineers will assess whether the building is stable enough for search dogs and rescue workers to be sent in.
The dangerous rescue mission — which has won support from both Prime Minister Stephen Harper and Ontario Premier Dalton McGuinty — would see the robotic arm deliberately topple some of the more fragile structures within the rubble of the mall.
Bill Neadles of the Heavy Urban Search and Rescue team said a precariously balanced escalator whose imminent collapse turned would-be rescuers away from the site on Monday will be demolished under strict supervision.
"Once we get this machine set up in front of the building, the arm will be able to reach up over top of the structure and plop itself down right on the floor," Neadles said. "It seems like that's kind of "Transformers" kind of stuff, but that's what they're assuring me we can do."
Once the escalator is out of the way and structural engineers give crews the green light to enter, crews will resume the laborious task of securing the structure as they edge towards the spot where they believe the victims are lying, about 12 metres from the south corner of the building.
Officials stressed, however, that the likelihood of finding survivors is increasingly slim.
No one has detected signs of life since Monday morning, Neadles said, adding the prognosis is not positive.
"Based on the information that we supplied him, [our doctor] was of the opinion that it was a very slim ability for that person to remain alive," said Neadles.
At least one person is confirmed dead after the roof of the shopping mall crashed through the two-floor building on Saturday afternoon. More than 20 people were injured, none of them seriously.
Meanwhile, the number of those still unaccounted for has been knocked down to 12, officials said Tuesday.
Ontario Provincial Police Insp. Percy Jollymore said officers are keeping a list of people reported missing, but said the numbers change frequently as community members make contact with their loved ones.
"We are getting calls basically from all around Canada. We're really looking for people who could be in the mall," Jollymore said. "We still cannot determine how many people are there. We just don't know."
Earlier in the day, both McGuinty and Elliot Lake residents voiced their determination to assist the rescue effort despite the disheartening odds.
"I thought it was important that we exercise every option, explore every possibility," McGuinty said. "I'm sure if that was your mom or your daughter or your brother, if somebody came to you and said, 'how far should we push,' I think we'd all say we need to go as far as we possibly can to rescue these individuals."
Community members agreed. Buoyed by renewed hope of saving survivors, they began organizing groups of volunteers willing to help with the operation.
Local residents were quick to voice their outrage on Monday after officials called off the rescue effort, loudly condemning crews for walking away from the operation too soon.
Rescuers had detected signs of life inside the mall earlier in the day, but aborted the search hours later after determining a secondary collapse was imminent.
That decision did not sit well with residents of this former mining hub, who gathered at city hall to voice their displeasure within moments of the announcement.
Among those hit hardest by the news was Rejean Aylwin, who said he believes his daughter Lucie Aylwin is inside.
"They just gave up," Aylwin said on Monday.
"It doesn't make sense. You can't give up. You've got to keep going until you find them."
Aylwin said he worked in a mine for 35 years and that culture among miners was to never leave someone to perish underground.
On Tuesday morning, at least 70 people had volunteered to assist with the renewed rescue effort.
Michael Croke said they're well-acquainted with the perils of such efforts.
The list of volunteers includes at least 30 former miners such as himself, as well as dozens of younger people willing to help remove rubble.
"We're not going in there blind and stupid," said Croke. "We'll go in there and do the same that they're doing. We'll check it out. But we also know the mall. Even though there's danger overhead, if you're in the rescue business, you've got to expect that kind of danger."
Catherine Timleck-Shaw said rescuers must remain optimistic if only for the sake of those who may have survived.
"As far as we're concerned, there's someone alive in there. And that person has a right to live," she said.
McGuinty said community members have the support of the entire province.
"They're not alone. We are 13 million Ontarians strong. They are part of the family," he said. "They have our prayers, but more than that, they have our active support."
- With files from Michelle McQuigge and Maria Babbage in Toronto.
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