Hooked up to an oxygen machine and seriously ill with heart and lung disease, Auckland woman Folole Muliaga pleaded "for a chance".
But her plea fell on deaf ears and a contractor cut off her power after saying he was "just doing his job".
About 2 1/2 hours later the 44-year-old mother of three was dead.
Mercury Energy has described the death as "an absolute tragedy" and has launched an internal investigation.
"We are deeply sympathetic to the family and acknowledge the tragedy that has occurred. However, we were simply unaware that loss of electricity to the household was putting a vulnerable customer at risk," said James Moulder, the general manager.
Mr Moulder said the contractor spoke to the family but was not told Mrs Muliaga could be put at risk. The dead woman's family, who were last night giving police a statement, strongly disagree.
Her son Ietitaia, 20, said the contractor knocked on the back door of their Mangere home at 11am on Tuesday, saying he was there to switch off the electricity because a bill of $168.40 had not been paid.
Mrs Muliaga - who was sitting in a chair with tubes running from an oxygen machine to her nose - wanted to speak to the contractor and so they discussed the matter in the lounge.
"She asked him to just give us a chance."
The family say they told the contractor they needed power to run Mrs Muliaga's machine, but the man was adamant.
"He says he was just doing his job."
The power was then cut. As the contractor spoke briefly again to Mrs Muliaga her oxygen machine's emergency warning blared, indicating it was about to shut down.
"He heard it but he just walked away," said Ietitaia.
In the two hours that followed Mrs Muliaga declined an offer by her family for an ambulance to be called.
About 1pm she indicated to her sons that she was "feeling different, dizzy" and asked for them to sing hymns for her.
Things quickly took a turn for the worse.
"It just happened quickly."
The look on her face said it all for Ietitaia.
"She couldn't speak at all.
"She knew it was not going to be good."
When she passed out at 1.32pm an ambulance was called. Her sons, untrained in CPR, tried to rouse their mother by slapping her lightly on her hands and face.
Twelve minutes later, when the ambulance arrived, she was dead.
Mrs Muliaga's nephew, Brenden Sheehan, said there was absolutely no doubt the contractor knew she was on oxygen and needed power to keep it running.
"We're angry at Mercury and the apparent actions of the company in coming and cutting off the power without giving her a chance to address the problem - particularly when I look at her power bill and there'd been two payments made in the last month. There's nothing in the bill about disconnection and it was only issued last Wednesday, so there's a lot of questions to be answered."
Mr Sheehan is further angered that the family were left to grieve in the dark on Tuesday night.
"I am told that Victim Support contacted the company and asked them to put the power on after our aunt had passed away, and they refused to do so until the bill was paid ... I don't believe the statements made by Mercury [yesterday morning] that they put the power back on to help the family - I think they put it back on to avoid public embarrassment."
The power was only reconnected at 8am yesterday - after Mr Sheehan, a union organiser, contacted Mercury's chief executive.
"He passed his condolences and he was appropriately remorseful but he didn't say sorry for the company's actions."
Mr Sheehan called for a full investigation by the company and police.
"Someone's died unnecessarily as a result of these actions and they need to be brought to account."
Mr Sheehan said they would have been in the same situation if there had been a standard power cut but "without all the upset that goes with it so they probably would have been more clear-headed in their thinking".
He said although Mrs Muliaga's breathing had been getting worse she told her young teenage son not to panic and to wait until her husband arrived home.
"That is a typical Samoan thing. They don't like their kids to be worried.
"The dad arrived when it was too late. She was basically dead before the ambulance got there, as far as we are aware."
Mr Moulder said the company deeply regretted Mrs Muliaga's death.
"Certainly personally me and everyone here has been deeply affected by it and our first thoughts naturally remain with the family. The family has lost a mother and this is an absolute tragedy, there's no other word for it."
Mr Moulder disputed the family's allegations that they were not sent reminder notices about the power being cut off, including the final 48-hour warning. "Our records show that those notices were sent."
Mr Moulder said the contractor's version of what happened at the house also differed from the family's but he would not discuss it.
When asked if it would not have been clear to the contractor that Mrs Muliaga had a medical problem, Mr Moulder said: "All I can say is that is not our understanding of the events and I would like to leave it there. I don't think it is appropriate to go into a hell of a lot more detail on this.
"In saying that, we do have procedures in place to deal with health issues."
Mr Moulder would not say if the contractor had contacted the call centre to discuss the matter before shutting off the power or what the procedures were when a contractor was in doubt.
VirCom EMS, the contracting company responsible for disconnecting the power, referred questions to Mercury.
VirCom chief executive Craig Shepherd said the company was "absolutely devastated for the family. This is not something we want to happen. My heart goes out to the family."
He refused to say if the electrician who cut the power had been stood down, but said the man was "devastated and we are counselling him at the present time".
Mercury promises to give seven days' notice of disconnection and a final warning no less than 24 hours beforehand.
Gas and Electricity Complaints Commissioner Judi Jones said if a company disconnected without warning the customer could complain to her.
The death of Mrs Muliaga was the first time she had heard of someone dying because their power was cut.
Folole Muliaga is discharged from Middlemore Hospital. She had been treated for heart and lung disease and had breathing difficulties related to obesity. She was given a mains-powered oxygen machine.
A Mercury Energy invoice dated May 23 sent to the Muliaga family shows they owe a discounted amount of $290.79 for power which is due for payment by June 13. The statement shows this includes a balance of $168.40 for the previous month's statement and $136 in current charges. The invoice also shows they paid $61.90 on May 1 and $45 on May 17.
At 11am on Tuesday, a contractor working for VirCom EMS, arrives at the family home in Mangere saying he is going to switch off the electricity because the outstanding $168.40 balance had not been paid. The family say they asked the contractor to leave the power on so the oxygen machine could work.
About 1pm, Mrs Muliaga asks her sons to sing to her as she feels unwell.
At 1.32pm, she passes out and an ambulance is called. Twelve minutes later the ambulance arrives but paramedics cannot revive Mrs Muliaga.
Mercury Energy says it was not aware that its actions in disconnecting the Muliaga's power supply could have potentially life-threatening consequences. It says its preliminary investigation suggests there was no indication given that disconnection would result in medical danger.
General manager James Moulder said throughout a six to seven-week process of disconnecting the home, and on the day in question, "we were not alerted that there was a person resident dependent on a medical device reliant on electricity".
Last night Mrs Muliaga's family gave a statement to police.
Family spokesman Brenden Sheehan described Mercury's rejection of the family's version of events as "disgraceful".